Particles comprising polyamides with pendent optical absorbers and related methods

ABSTRACT

A method for producing highly spherical polymer particles comprising a polyamide having an optical absorber pendent from a backbone of the polyamide (OAMB-polyamide) may comprise: mixing a mixture comprising the OAMB-polyamide, a carrier fluid that is immiscible with the OAMB-polyamide, and optionally an emulsion stabilizer at a temperature greater than a melting point or softening temperature of the OAMB-polyamide and at a shear rate sufficiently high to disperse the OAMB-polyamide in the carrier fluid; and cooling the mixture to below the melting point or softening temperature of the OAMB-polyamide to form particles comprising the OAMB-polyamide and the emulsion stabilizer, when present, associated with an outer surface of the particles.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of priority under 35 U. S. C.§ 119 from U.S. Provisional Patent Application 62/897,534, filed on Sep.9, 2019 and incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to compositions, synthesis methods, andapplications of polyamides having an optical absorber pendent from thebackbone of the polyamide. For example, particles may comprise apolyamide having an optical absorber pendent from the backbone of thepolyamide.

BACKGROUND

Thermoplastic polymers are often used to make extruded objects likefilms, bags, particles, and filaments. One example of a thermoplasticpolymer is a polyamide. Polyamides like nylons are off-white coloredpolymers that have the ability to withstand elevated or low temperatureswithout loss of physical properties. Therefore, objects formed withpolyamides can be used in demanding applications like power tools,automotive parts, gears, and appliance parts. In some instances, theapplication may call for the polyamide-made part to be colored. Becausepigments are particulates, pigments can be difficult to homogeneouslymix in the polyamide, which causes the coloring of the resultant part tobe uneven.

One application where homogeneous incorporation of pigments isespecially important is the rapidly growing technology area ofthree-dimensional (3-D) printing, also known as additive manufacturing.Although 3-D printing has traditionally been used for rapid prototypingactivities, this technique is being increasingly employed for producingcommercial and industrial objects, which may have entirely differentstructural and mechanical tolerances than do rapid prototypes.

3-D printing operates by depositing either (a) small droplets or streamsof a melted or solidifiable material or (b) powder particulates inprecise deposition locations for subsequent consolidation into a largerobject, which may have any number of complex shapes. Such deposition andconsolidation processes typically occur under the control of a computerto afford layer-by-layer buildup of the larger object. In a particularexample, consolidation of powder particulates may take place in a 3-Dprinting system using a laser to promote selective laser sintering(SLS).

Powder particulates usable in 3-D printing include thermoplasticpolymers, including thermoplastic elastomers, metals and othersolidifiable substances. One example thermoplastic polymer is nylon.Nylons are off-white colored polymers that have the ability to withstandelevated or low temperatures without loss of physical properties.Therefore, nylons can be used in demanding applications like powertools, automotive parts, gears, and appliance parts.

When using a particulate pigment in 3-D printing, the particulatesshould be evenly dispersed throughout the small melted droplets or thepower particulate, or the coloring of the final object will be uneven.

SUMMARY OF INVENTION

The present disclosure relates to compositions, synthesis methods, andapplications of polyamides having an optical absorber pendent from thebackbone of the polyamide. For example, particles may comprise apolyamide having an optical absorber pendent from the backbone of thepolyamide.

Disclosed herein are methods that comprise: esterifying ahydroxyl-pendent optical absorber with a halogen-terminal aliphatic acidto yield a halogen-terminal alkyl-optical absorber; and N-alkylating apolyamide with the halogen-terminal alkyl-optical absorber to yield apolyamide having an optical absorber pendent from the polyamide'sbackbone (OAMB-polyamide).

Disclosed herein are methods that comprise: esterifying acarboxyl-pendent optical absorber with a halogen-terminal aliphaticalcohol to yield a halogen-terminal alkyl-optical absorber; andN-alkylating a polyamide with the modified optical absorber to yield anOAMB-polyamide.

Disclosed herein are articles that comprise: a polyamide having anoptical absorber pendent from a backbone of the polyamide producedaccording to the methods described herein.

Disclosed herein are methods that comprise: extruding a polymer meltcomprising the polyamide produced according to the methods describedherein through an orifice to produce a film, a fiber (or a filament),particles, pellets, or the like.

Disclosed herein are compositions that comprise: a polyamide having anoptical absorber pendent from a backbone of the polyamide, wherein thepolyamide and the optical absorber are connected by an alkyl linker.

Disclosed herein are articles that comprise: a polyamide having anoptical absorber pendent from a backbone of the polyamide, wherein thepolyamide and the optical absorber are connected by an alkyl linker.

Disclosed herein are methods that comprise: extruding a polymer meltcomprising a polyamide having an optical absorber pendent from abackbone of the polyamide, wherein the polyamide and the opticalabsorber are connected by an alkyl linker, through an orifice to producea film, a fiber (or a filament), particles, pellets, or the like.

Disclosed herein are methods that comprise: mixing a mixture comprisingan OAMB-polyamide, a carrier fluid that is immiscible with theOAMB-polyamide, and optionally an emulsion stabilizer at a temperaturegreater than a melting point or softening temperature of theOAMB-polyamide and at a shear rate sufficiently high to disperse theOAMB-polyamide in the carrier fluid; and cooling the mixture to belowthe melting point or softening temperature of the OAMB-polyamide to formsolidified particles comprising the OAMB-polyamide and the emulsionstabilizer, when present, associated with an outer surface of thesolidified particles.

Disclosed herein are compositions that comprise: particles comprising anOAMB-polyamide and having a circularity of about 0.90 to about 1.0.

Also disclosed herein are methods that comprise: depositingOAMB-polyamide particles described herein optionally in combination withother thermoplastic polymer particles upon a surface in a specifiedshape; and once deposited, heating at least a portion of the particlesto promote consolidation thereof and form a consolidated body.

BRIEF DESCRIPTION OF THE DRAWINGS

The following FIGURES are included to illustrate certain aspects of thedisclosure, and should not be viewed as exclusive configurations. Thesubject matter disclosed is capable of considerable modifications,alterations, combinations, and equivalents in form and function, as willoccur to those skilled in the art and having the benefit of thisdisclosure.

The FIGURE is a flow chart of a nonlimiting example method of thepresent disclosure.

DETAILED DESCRIPTION

The present disclosure relates to polyamides having an optical absorberpendent from the backbone of the polyamide and related methods. Morespecifically, the methods herein first esterify an optical absorber witha halogen-terminal alkyl by forming an ester bond between (a) ahalogen-terminal aliphatic acid or a halogen-terminal alcohol and (b) ahydroxyl group or carboxyl group, respectively, of the optical absorberto yield a halogen-terminal alkyl-optical absorber. Then, the polyamidebackbone is alkylated with the halogen-terminal alkyl-optical absorber.The result is a polyamide having an optical absorber pendent from thebackbone of the polyamide, also referred to herein as an opticalabsorber-modified backbone of a polyamide or OAMB-polyamide. Because theoptical absorber is pendent from the backbone of the polyamide, objectsproduced by additive manufacturing methods that include these particlesshould maintain an even color over time because the optical absorbercannot migrate within or leach from the object.

The present disclosure also relates to particles comprising a polyamidehaving an optical absorber pendent from the backbone of the polyamide(also referred to herein as an optical absorber-modified backbone of apolyamide or OAMB-polyamide) and related methods. More specifically, thepresent disclosure includes methods of making highly spherical polymerparticles comprising the one or more OAMB-polyamides and optionally oneor more other thermoplastic polymers. Said polymer particles may beuseful, among other things, as starting material for additivemanufacturing.

The polymer particles described herein are produced by meltemulsification methods where one or more OAMB-polyamides and optionallyone or more additional thermoplastic polymers are dispersed as a melt ina carrier fluid that is immiscible with the OAMB-polyamide andadditional thermoplastic polymers, if used. A sufficient amount of shearis applied to the mixture to cause the polymer melt to form droplets inthe carrier fluid.

Because the optical absorber is pendent from the backbone of thepolyamide, objects produced by additive manufacturing methods thatinclude these particles should maintain an even color over time becausethe optical absorber cannot migrate within or leach from the object.

Definitions and Test Methods

As used herein, the term “immiscible” refers to a mixture of componentsthat, when combined, form two or more phases that have less than 5 wt %solubility in each other at ambient pressure and at room temperature orthe melting point of the component if it is solid at room temperature.For example, polyethylene oxide having 10,000 g/mol molecular weight isa solid at room temperature and has a melting point of 65° C. Therefore,said polyethylene oxide is immiscible with a material that is liquid atroom temperature if said material and said polyethylene oxide have lessthan 5 wt % solubility in each other at 65° C.

As used herein, the term “optical absorber” refers to a molecule orportion thereof that absorbs ultraviolet or visible light.

As used herein, the term “chromophore” refers to an optical absorberwhere the light absorption imparts color.

As used herein, the term “fluorophore” refers to an optical absorberthat re-emits an absorbed photon at a different wavelength.

As used herein, the term “thermoplastic polymer” refers to a plasticpolymer material that softens and hardens reversibly on heating andcooling. Thermoplastic polymers encompass thermoplastic elastomers.

As used herein, the term “elastomer” refers to a copolymer comprising acrystalline “hard” section and an amorphous “soft” section. In the caseof a polyurethane, the crystalline section may include a portion of thepolyurethane comprising the urethane functionality and optional chainextender group, and the soft section may include the polyol, forinstance.

As used herein, the term “polyurethane” refers to a polymeric reactionproduct between a diisocyanate, a polyol, and an optional chainextender.

As used herein, the term “oxide” refers to both metal oxides andnon-metal oxides. For purposes of the present disclosure, silicon isconsidered to be a metal.

As used herein, the terms “associated,” “association,” and grammaticalvariations thereof between emulsion stabilizers and a surface refers tochemical bonding and/or physical adherence of the emulsion stabilizersto the surface. Without being limited by theory, it is believed that theassociations described herein between polymers and emulsion stabilizersare primarily physical adherence via hydrogen bonding and/or othermechanisms. However, chemical bonding may be occurring to some degree.

As used herein, the term “embed” relative to nanoparticles and a surfaceof a polymer particle refers to the nanoparticle being at leastpartially extended into the surface such that polymer is in contact withthe nanoparticle to a greater degree than would occur if thenanoparticle were simply laid on the surface of the polymer particle.

Herein, D10, D50, D90, and diameter span are primarily used herein todescribe particle sizes. As used herein, the term “D10” refers to adiameter at which 10% of the sample (on a volume basis unless otherwisespecified) is comprised of particles having a diameter less than saiddiameter value. As used herein, the term “D50” refers to a diameter atwhich 50% of the sample (on a volume basis unless otherwise specified)is comprised of particles having a diameter less than said diametervalue. As used herein, the term “D90” refers to a diameter at which 90%of the sample (on a volume basis unless otherwise specified) iscomprised of particles having a diameter less than said diameter value.

As used herein, the terms “diameter span” and “span” and “span size”when referring to diameter provides an indication of the breadth of theparticle size distribution and is calculated as (D90-D10)/D50 (againeach D-value is based on volume, unless otherwise specified).

Particle size can be determined by light scattering techniques using aMalvern MASTERSIZER™ 3000 or analysis of optical digital micrographs.Unless otherwise specified, light scattering techniques are used foranalyzing particle size.

For light scattering techniques, the control samples were glass beadswith a diameter within the range of 15 μm to 150 μm under the tradenameQuality Audit Standards QAS4002™ obtained from Malvern Analytical Ltd.Samples were analyzed as dry powders, unless otherwise indicated. Theparticles analyzed were dispersed in air and analyzed using the AERO Sdry powder dispersion module with the MASTERSIZER™ 3000. The particlesizes were derived using instruments software from a plot of volumedensity as a function of size.

Particle size measurement and diameter span can also be determined byoptical digital microscopy. The optical images are obtained using aKeyence VHX-2000 digital microscope using version 2.3.5.1 software forparticle size analysis (system version 1.93).

As used herein, when referring to sieving, pore/screen sizes aredescribed per U.S.A. Standard Sieve (ASTM E11-17).

As used herein, the terms “circularity” and “sphericity” relative to theparticles refer to how close the particle is to a perfect sphere. Todetermine circularity, optical microscopy images are taken of theparticles. The perimeter (P) and area (A) of the particle in the planeof the microscopy image is calculated (e.g., using a SYSMEX FPIA 3000particle shape and particle size analyzer, available from MalvernInstruments). The circularity of the particle is C_(EA)/P, where C_(EA)is the circumference of a circle having the area equivalent to the area(A) of the actual particle.

As used herein, the term “shear” refers to stirring or a similar processthat induces mechanical agitation in a fluid.

As used herein, the term “aspect ratio” refers to length divided bywidth, wherein the length is greater than the width.

The melting point of a polymer, unless otherwise specified, isdetermined by ASTM E794-06(2018) with 10° C./min. ramping and coolingrates.

The softening temperature or softening point of a polymer, unlessotherwise specified, is determined by ASTM D6090-17. The softeningtemperature can be measured by using a cup and ball apparatus availablefrom Mettler-Toledo using a 0.50 gram sample with a heating rate of 1°C./min.

Angle of repose is a measure of the flowability of a powder. Angle ofrepose measurements were determined using a Hosokawa Micron PowderCharacteristics Tester PT-R using ASTM D6393-14 “Standard Test Methodfor Bulk Solids” Characterized by “Carr Indices.”

Hausner ratio (H_(r)) is a measure of the flowability of a powder and iscalculated by H_(r)=ρ_(tap)/ρ_(bulk), where ρ_(bulk) is the bulk densityper ASTM D6393-14 and ρ_(tap) is the tapped density per ASTM D6393-14.

As used herein, viscosity of carrier fluids is the kinematic viscosityat 25° C., unless otherwise specified, measured per ASTM D445-19. Forcommercially procured carrier fluids (e.g., PDMS oil), the kinematicviscosity data cited herein was provided by the manufacturer, whethermeasured according to the foregoing ASTM or another standard measurementtechnique.

Optical Absorber-Modified Polyamides

The present disclosure relates to polyamides having an optical absorberpendent from the backbone of the polyamide and related methods.

Examples of polyamides include, but are not limited to, polycaproamide(nylon 6, polyamide 6, or PA6), poly(hexamethylene succinamide) (nylon4,6, polyamide 4,6, or PA4,6), polyhexamethylene adipamide (nylon 6,6,polyamide 6,6, or PA6,6), polypentamethylene adipamide (nylon 5,6,polyamide 5,6, or PA5,6), polyhexamethylene sebacamide (nylon 6,10,polyamide 6,10, or PA6,10), polyundecamide (nylon 11, polyamide 11, orPA11), polydodecamide (nylon 12, polyamide 12, or PA12), andpolyhexamethylene terephthalamide (nylon 6T, polyamide 6T, or PA6T),nylon 10,10 (polyamide 10,10 or PA10,10), nylon 10,12 (polyamide 10,12or PA10,12), nylon 10,14 (polyamide 10,14 or PA10,14), nylon 10,18(polyamide 10,18 or PA10,18), nylon 6,18 (polyamide 6,18 or PA6,18),nylon 6,12 (polyamide 6,12 or PA6,12), nylon 6,14 (polyamide 6,14 orPA6,14), nylon 12,12 (polyamide 12,12 or PA12,12), semi-aromaticpolyamide, aromatic polyamides (aramides), and the like, and anycombination thereof. Copolyamides may also be used. Examples ofcopolyamides include, but are not limited to, PA 11/10,10, PA 6/11, PA6,6/6, PA 11/12, PA 10,10/10,12, PA 10,10/10,14, PA 11/10,36, PA11/6,36, PA 10,10/10,36, PA 6T/6,6, and the like, and any combinationthereof. Examples of polyamide elastomers include, but are not limitedto, polyesteramide, polyetheresteramide, polycarbonate-esteramide, andpolyether-block-amide elastomers. Herein, a polyamide followed by asingle number is a polyamide having that number of backbone carbonsbetween each nitrogen. A polyamide followed by a first number commasecond number is a polyamide having the first number of backbone carbonsbetween the nitrogens for the section having no pendent=0 and the secondnumber of backbone carbons being between the two nitrogens for thesection having the pendent=0. By way of nonlimiting example, nylon 6,10is [NH—(CH₂)₆—NH—CO—(CH₂)₈—CO]_(n). A polyamide followed by number(s)backslash number(s) are a copolymer of the polyamides indicated by thenumbers before and after the backslash.

Optical absorbers may be from known families including, but not limitedto, rhodamines, fluoresceins, coumarins, naphthalimides, benzoxanthenes,acridines, cyanines, oxazins, phenanthridine, pyrrole ketones,benzaldehydes, polymethines, triarylmethanes, anthraquinones,pyrazolones, quinophthalones, carbonyl dyes, diazo dyes, perinones,diketopyrrolopyrrole (DPP), dioxazine dyes, phthalocyanines,indanthrenes, benzanthrone, violanthrones, azo dyes, phthalocyaninedyes, quinacridone dyes, anthraquinone dyes, dioxagine dyes, indigodyes, thioindigo dyes, perinone dyes, perylene dyes, isoindolene dyes,aromatic amino acids, flavins, derivatives of pyridoxyl, derivatives ofchlorophyll, and the like, and any combination thereof. Opticalabsorbers should be chosen to be hydroxyl-pendent and/orcarboxyl-pendent based on the synthesis scheme implemented.

In a first nonlimiting example embodiment of the present disclosure, anOAMB-polyamide may be produced by esterifying a hydroxyl-pendent opticalabsorber with a halogen-terminal aliphatic acid to yield ahalogen-terminal alkyl-optical absorber; and reacting a polyamide withthe halogen-terminal alkyl-optical absorber to yield an OAMB-polyamide.

In a second nonlimiting example embodiment of the present disclosure, anOAMB-polyamide may be produced by esterifying a carboxyl-pendent opticalabsorber with a halogen-terminal aliphatic alcohol to yield ahalogen-terminal alkyl-optical absorber; and reacting a polyamide withthe halogen-terminal alkyl-optical absorber to yield an OAMB-polyamide.Herein, anhydride moieties are considered carboxylic acid moietiesbecause the anhydrides open to carboxylic acids during synthesis.

Scheme 1 is a nonlimiting example of a hydroxyl-pendent optical absorber(illustrated specifically as alizarin) reaction with a C₂ to C₁₈halogen-terminal aliphatic acid (illustrated as a bromo-substitutedaliphatic acid where n is 1 to 17) to yield a halogen-terminalalkyl-optical absorber.

Examples of hydroxyl-pendent optical absorbers include, but are notlimited to, 1,2-dihydroxyanthraquinone (also known as alizarin);carminic acid; 1,3-dihydroxyanthraquinone; 1,4-dihydroxyanthraquinone;1-hydroxy-4-(p-tolylamino)anthraquinone (also known as oil violet andSolvent Violet 13); 1,8-dihydroxy-3-methoxy-6-methylanthraquinone (alsoknown as parietin); 1,2,5-trihydroxy-6-methylanthracene-9,10-dione (alsoknown as morindone); calcein (also known as flourexon);6-carboxyfluorescein succinimidyl ester; 6-carboxyfluorescein (alsoknown as 6-FAM);2′,7′-dichloro-3′,6′-dihydroxy-3H-spiro[2-benzofuran-1,9′-xanthen]-3-one(also known as dichlorofluoresceine); fluorescein isothiocyanate;4′,5′-dibromofluorescein; 5(6)-carboxy-2′,7′-dichlorofluorescein;4-chloro-3-[(2Z)-2-[1-[5-chloro-4-[[(2Z)-2-[[2-chloro-5-[N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]-C-hydroxycarbonimidoyl]phenyl]hydrazinylidene]-3-oxobutanoyl]amino]-2-methylanilino]-1,3-dioxobutan-2-ylidene]hydrazinyl]-N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]benzenecarboximidicacid (also known as Disazo Yellow GG and Pigment Yellow 128);2-[(3-carboxy-2-oxidonaphthalen-1-yl)diazenyl]-4-chloro-5-methylbenzenesulfonatedisodium (also known as Wachtung Red B and Pigment Red 48); phenol dyes;3,3-bis(4-hydroxyphenyl)-2-benzofuran-1-one (also known asphenolphthalein);4,8-diamino-1,5-dihydroxy-9,10-dioxoanthracene-2-sulfonate sodium (alsoknown as Acid Blue 43); 1-amino-4-hydroxy-2-phenoxyanthracene-9,10-dione(also known as Disperse Red 60);5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylatetrisodium (also known as tartrazine);5-chloro-2-hydroxy-3-[(3-methyl-5-oxo-1-phenyl-4H-pyrazol-4-yl)diazenyl]benzenesulfonatesodium (also known as mordant red 19);2-[(4-hydroxy-9,10-dioxoanthracen-1-yl)amino]-5-methylbenzenesulfonicacid sodium (also known as alizarin irisol r);3,5,6,8-tetrahydroxy-1-methyl-9,10-dioxo-7-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]anthracene-2-carboxylicacid (also known as carmine); and the like; and any combination thereof.

Preferably the hydroxyl-pendent optical absorbers have one or twohydroxyls. Examples of hydroxyl-pendent optical absorbers include, butare not limited to, alizarin; 1,3-dihydroxyanthraquinone;1,4-dihydroxyanthraquinone; 1,2,4-trihydroxyanthraquinone;1-hydroxy-4-(p-tolylamino)anthraquinone;1,8-dihydroxy-3-methoxy-6-methylanthraquinone; calcein;6-carboxyfluorescein succinimidyl ester; 6-carboxyfluorescein;2′,7′-dichloro-3′,6′-dihydroxy-3H-spiro[2-benzofuran-1,9′-xanthen]-3-one;fluorescein isothiocyanate; 4′,5′-dibromofluorescein;4-chloro-3-[(2Z)-2-[1-[5-chloro-4-[[(2Z)-2-[[2-chloro-5-[N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]-C-hydroxycarbonimidoyl]phenyl]hydrazinylidene]-3-oxobutanoyl]amino]-2-methylanilino]-1,3-dioxobutan-2-ylidene]hydrazinyl]-N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]benzenecarboximidicacid;2-[(3-carboxy-2-oxidonaphthalen-1-yl)diazenyl]-4-chloro-5-methylbenzenesulfonatedisodium; phenol dyes; 3,3-bis(4-hydroxyphenyl)-2-benzofuran-1-one;4,8-diamino-1,5-dihydroxy-9,10-dioxoanthracene-2-sulfonate sodium;1-amino-4-hydroxy-2-phenoxyanthracene-9,10-dione;5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylatetrisodium;5-chloro-2-hydroxy-3-[(3-methyl-5-oxo-1-phenyl-4H-pyrazol-4-yl)diazenyl]benzenesulfonatesodium;2-[(4-hydroxy-9,10-dioxoanthracen-1-yl)amino]-5-methylbenzenesulfonicacid sodium; and the like; and any combination thereof.

C₂ to C₁₈ halogen-terminal aliphatic acids may have the generalstructure of X—(CH₂)_(n)—COOH where X is bromo or chloro (probablybromo) and n is 1-17 (preferably 1-5). Specific examples of C₂ to C₁₈halogen-terminal aliphatic acids include, but are not limited to,bromoacetic acid, chloroacetic acid, 3-bromopropionic acid,3-chloropropionic acid, 4-bromobutyric acid, 4-chlorobutyric acid,5-bromovaleric acid, 5-chlorovaleric acid, 6-bromohexanoic acid,6-chlorohexanoic acid, bromo-polyethyleneglycol i-carboxylic acid(bromo-PEG₁-acid), bromo-PEG₂-acid, bromo-PEG₃-acid, bromo-PEG₄-acid,bromo-PEG₅-acid, bromo-PEG₁-CH₂COOH, bromo-PEG₃-CH₂COOH, and the like,and any combination thereof.

Scheme 2 is a nonlimiting example of a carboxyl-pendent optical absorber(illustrated specifically as 6-carboxyfluorescein) reaction with a C₂ toC₁₈ halogen-terminal aliphatic alcohol (illustrated as abromo-substituted aliphatic alcohol where n is 1 to 17) to yield ahalogen-terminal alkyl-optical absorber. Herein, anhydride moieties areconsidered carboxylic acid moieties because the anhydrides open tocarboxylic acids during synthesis.

Examples of carboxyl-pendent optical absorbers include, but are notlimited to, calcein (also known as flourexon); 5(6)-carboxyfluorescein;6-carboxyfluorescein (also known as 6-FAM);5(6)-carboxyfluorescein-N-hydroxysuccinimide ester; 2-pyrenepropanoicacid; 2-perylenepropanoic acid; 3,9-perylenedicarboxylic acid;5(6)-carboxy-2,7′-dichlorofluorescein; calcein blue;2-[(3-carboxy-2-oxidonaphthalen-1-yl)diazenyl]-4-chloro-5-methylbenzenesulfonatedisodium;5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylatetrisodium; and the like; and any combination thereof.

Preferably, the carboxyl-pendent optical absorbers have one or twocarboxyls. Examples of such carboxyl-pendent optical absorbers include,but are not limited to, 5(6)-carboxyfluorescein; 6-carboxyfluorescein;5(6)-carboxyfluorescein-N-hydroxysuccinimide ester; 2-pyrenepropanoicacid; 2-perylenepropanoic acid; 3,9-perylenedicarboxylic acid;5(6)-carboxy-2,7′-dichlorofluorescein; calcein blue;2-[(3-carboxy-2-oxidonaphthalen-1-yl)diazenyl]-4-chloro-5-methylbenzenesulfonatedisodium;5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylatetrisodium; and the like; and any combination thereof.

C₂ to C₁₈ halogen-terminal aliphatic alcohols may have the generalstructure of X—(CH₂)_(n)—OH where X is bromo or chloro (probably bromo)and n is 2-18 (preferably 2-6). Specific examples of C₂ to C₁₈halogen-terminal aliphatic alcohols include, but are not limited to,3-bromoethan-1-ol, 3-chloroethan-1-ol, 4-bromopropan-1-ol,4-chloropropan-1-ol, 5-bromopbutan-1-ol, 5-chlorobutan-1-ol,6-bromopentan-1-ol, 6-chloropentan-1-ol, 7-bromohexan-1-ol,7-chlorohexan-1-ol, and the like, and any combination thereof.

Esterification in Scheme 1 or Scheme 2 may be achieved with Steglichesterification, which uses dicyclohexylcarbodiimide (DCC) as a couplingreagent and 4-dimethylaminopyridine (DMAP) as a catalyst.

The esterification in Scheme 1 or Scheme 2 may be performed at about 0°C. to about 70° C. (or about 0° C. to about 30° C., or about 20° C. toabout 40° C., or about 30° C. to about 70° C.).

The esterification in Scheme 1 or Scheme 2 may be performed for about 10minutes to about 24 hours (or about 10 minutes to about 6 hours, orabout 2 hours to about 12 hours, or about 6 hours to about 24 hours).

The esterification in Scheme 1 or Scheme 2 may be performed in a solventthat includes, but is not limited to, dichloromethane, dimethylsulfoxide (DMSO), N,N-dimethylformamide, acetonitrile, tetrahydrofuran,and the like, and any combination thereof.

The molar ratio of the hydroxyl-pendent optical absorber to thehalogen-terminal aliphatic acid is preferably about 5:1 to about 1:5 (orabout 5:1 to about 1:5, or about 5:1 to about 1:5, or about 5:1 to about1:5). The molar ratio of the carboxyl-pendent optical absorber to thehalogen-terminal aliphatic alcohol is preferably about 5:1 to about 1:5(or about 5:1 to about 1:5, or about 5:1 to about 1:5, or about 5:1 toabout 1:5).

Generally, the foregoing molar ratios are preferably at or close toabout 1:1 (e.g., about 2:1 to about 1:2) because many of the opticalabsorbers have more than one hydroxyl group or more than one carboxylgroup. Being at or close to about 1:1 molar ratio mitigates esterifyingthe optical absorber at more than one location, which would yield ahalogen-terminal alkyl-optical absorber that is likely to act as acrosslinker when reacted with a polyamide.

After the halogen-terminal alkyl-optical absorber is formed by Scheme 1or Scheme 2, a polyamide is N-alkylated with the halogen-terminalalkyl-optical absorber. Continuing with the nonlimiting example inScheme 1, Scheme 3 illustrates a reaction between the halogen-terminalalkyl-optical absorber (halogen-terminal alkyl-alizarin) and a polyamide(illustrated as nylon 6) to yield an OAMB-polyamide (illustrated as analizarin-pendent nylon 6).

N-alkylation in Scheme 3 is performed in the presence of a strong base.Examples of strong bases include, but are not limited to, sodiumt-butoxide, potassium t-butoxide, magnesium t-butoxide, calciumt-butoxide, sodium t-amylate, sodium 2-methyl-2-butoxide, alkali metalamides (e.g., sodium amide, potassium amide, lithium diethylamide, andlithium diisopropylamide), sodium hydride, lithium hydride,triphenylmethyl lithium, triphenylmethyl sodium, naphthalene sodium,triphenylmethyl potassium, and the like, and any combination thereof.

The N-alkylation in Scheme 3 may be performed at about 100° C. to about200° C. (or about 100° C. to about 150° C., or about 125° C. to about175° C., or about 150° C. to about 200° C.).

The N-alkylation in Scheme 3 may be performed for about 10 minutes toabout 48 hours (or about 10 minutes to about 6 hours, or about 2 hoursto about 12 hours, or about 6 hours to about 24 hours, or about 12 hoursto about 48 hours).

The N-alkylation in Scheme 3 may be performed in a solvent thatincludes, but is not limited to, DMSO, benzylalcohol, nitrobenzene,nitroalcohol, and the like, and any combination thereof.

The molar ratio of the halogen-terminal alkyl-optical absorber to thepolyamide is preferably about 500:1 to about 10:1 (or about 500:1 toabout 100:1, or about 250:1 to about 50:1, or about 100:1 to about10:1).

The product of Scheme 3 is a polyamide having an optical absorberpendent from a backbone of the polyamide, wherein the polyamide and theoptical absorber are connected by an alkyl linker preferably having 2-18carbons, more preferably 2-6 carbons. One skilled in the art willrecognize that Schemes 1, 2, and 3 can be adapted to other opticalabsorbers and other polyamides to yield various OAMB-polyamides.Compounds 1-7 are nonlimiting examples of OAMB-polyamides.

Applications of OAMB-Polyamides

The OAMB-polyamides described herein may be used to produce a variety ofobjects (or articles). The OAMB-polyamides described herein may be usedalone or in combination with other thermoplastic polymers (e.g.,polyamides without an optical absorber and/or other thermoplasticpolymers). Examples of thermoplastic polymers that may be used inconjunction with one or more OAMB-polyamides of the present disclosureinclude, but are not limited to, polyamides, polyurethanes,polyethylenes, polypropylenes, polyacetals, polycarbonates, polybutyleneterephthalate (PBT), polyethylene terephthalate (PET), polyethylenenaphthalate (PEN), polytrimethylene terephthalate (PTT),polyhexamethylene terephthalate, polystyrenes, polyvinyl chlorides,polytetrafluoroethenes, polyesters (e.g., polylactic acid), polyethers,polyether sulfones, polyetherether ketones, polyacrylates,polymethacrylates, polyimides, acrylonitrile butadiene styrene (ABS),polyphenylene sulfides, vinyl polymers, polyarylene ethers, polyarylenesulfides, polysulfones, polyether ketones, polyamide-imides,polyetherimides, polyetheresters, copolymers comprising a polyetherblock and a polyamide block (PEBA or polyether block amide), grafted orungrafted thermoplastic polyolefins, functionalized or nonfunctionalizedethylene/vinyl monomer polymer, functionalized or nonfunctionalizedethylene/alkyl (meth)acrylates, functionalized or nonfunctionalized(meth)acrylic acid polymers, functionalized or nonfunctionalizedethylene/vinyl monomer/alkyl (meth)acrylate terpolymers, ethylene/vinylmonomer/carbonyl terpolymers, ethylene/alkyl (meth)acrylate/carbonylterpolymers, methylmethacrylate-butadiene-styrene (MBS)-type core-shellpolymers, polystyrene-block-polybutadiene-block-poly(methylmethacrylate) (SBM) block terpolymers, chlorinated or chlorosulphonatedpolyethylenes, polyvinylidene fluoride (PVDF), phenolic resins,poly(ethylene/vinyl acetate)s, polybutadienes, polyisoprenes, styrenicblock copolymers, polyacrylonitriles, silicones, and the like, and anycombination thereof. Copolymers comprising one or more of the foregoingmay also be used in the methods and systems described herein.

If needed, compatibilizers may be used when combining theOAMB-polyamides described herein with other thermoplastic polymers.Compatibilizers may improve the blending efficiency and/or efficacy ofthe polymers. Examples of polymer compatibilizers include, but notlimited to, PROPOLDER™ MPP2020 20 (polypropylene, available fromPolygroup Inc.), PROPOLDER™ MPP2040 40 (polypropylene, available fromPolygroup Inc.), NOVACOM™ HFS2100 (maleic anhydride functionalized highdensity polyethylene polymer, available from Polygroup Inc.), KEN-REACT™CAPS™ L™ 12/L (organometallic coupling agent, available from KenrichPetrochemicals), KEN-REACT™ CAPOW™ L™ 12/H (organometallic couplingagent, available from Kenrich Petrochemicals), KEN-REACT™ LICA™ 12(organometallic coupling agent, available from Kenrich Petrochemicals),KEN-REACT™ CAPS™ KPR™ 12/LV (organometallic coupling agent, availablefrom Kenrich Petrochemicals), KEN-REACT™ CAPOW™ KPR™ 12/H(organometallic coupling agent, available from Kenrich Petrochemicals),KEN-REACT™ titanates & zirconates (organometallic coupling agent,available from Kenrich Petrochemicals), VISTAMAXX™ (ethylene-propylenecopolymers, available from ExxonMobil), SANTOPRENE™ (thermoplasticvulcanizate of ethylene-propylene-diene rubber and polypropylene,available from ExxonMobil), VISTALON™ (ethylene-propylene-diene rubber,available from ExxonMobil), EXACT™ (plastomers, available fromExxonMobil) EXXELOR™ (polymer resin, available from ExxonMobil),FUSABOND™ M603 (random ethylene copolymer, available from Dow),FUSABOND™ E226 (anhydride modified polyethylene, available from Dow),BYNEL™ 41E710 (coextrudable adhesive resin, available from Dow), SURLYN™1650 (ionomer resin, available from Dow), FUSABOND™ P353 (a chemicallymodified polypropylene copolymer, available from Dow), ELVALOY™ PTW(ethylene terpolymer, available from Dow), ELVALOY™ 3427AC (a copolymerof ethylene and butyl acrylate, available from Dow), LOTADER™ AX8840(ethylene acrylate-based terpolymer, available from Arkema), LOTADER™3210 (ethylene acrylate-based terpolymer, available from Arkema),LOTADER™ 3410 (ethylene acrylate-based terpolymer, available fromArkema), LOTADER™ 3430 (ethylene acrylate-based terpolymer, availablefrom Arkema), LOTADER™ 4700 (ethylene acrylate-based terpolymer,available from Arkema), LOTADER™ AX8900 (ethylene acrylate-basedterpolymer, available from Arkema), LOTADER™ 4720 (ethyleneacrylate-based terpolymer, available from Arkema), BAXXODUR™ EC 301(amine for epoxy, available from BASF), BAXXODUR™ EC 311 (amine forepoxy, available from BASF), BAXXODUR™ EC 303 (amine for epoxy,available from BASF), BAXXODUR™ EC 280 (amine for epoxy, available fromBASF), BAXXODUR™ EC 201 (amine for epoxy, available from BASF),BAXXODUR™ EC 130 (amine for epoxy, available from BASF), BAXXODUR™ EC110 (amine for epoxy, available from BASF), styrenics, polypropylene,polyamides, polycarbonate, EASTMAN™ G-3003 (a maleic anhydride graftedpolypropylene, available from Eastman), RETAIN™ (polymer modifieravailable from Dow), AMPLIFY TY™ (maleic anhydride grafted polymer,available from Dow), INTUNE™ (olefin block copolymer, available fromDow), and the like, and any combination thereof.

Methods for producing objects include, but are not limited to, meltextrusion, injection molding, compression molding, melt spinning, meltemulsification, spray drying (e.g., to form particles), cryogenicmilling (or cryogenic grinding), freeze drying polymer dispersions,precipitation of polymer dispersions, and the like, and any hybridthereof.

Examples of articles that may be produced by such methods where theOAMB-polyamide may be all or a portion of said articles include, but arenot limited to, particles, films, packaging, toys, household goods,automotive parts, aerospace/aircraft-related parts, containers (e.g.,for food, beverages, cosmetics, personal care compositions, medicine,and the like), shoe soles, furniture parts, decorative home goods,plastic gears, screws, nuts, bolts, cable ties, jewelry, art, sculpture,medical items, prosthetics, orthopedic implants, production of artifactsthat aid learning in education, 3-D anatomy models to aid in surgeries,robotics, biomedical devices (orthotics), home appliances, dentistry,electronics, sporting goods, and the like. Further, particles may beuseful in applications that include, but are not limited to, paints,powder coatings, ink jet materials, electrophotographic toners, 3-Dprinting, and the like.

The OAMB-polyamides described herein may have a specific chemicalfingerprint that is useful in identifying objects, tracking objects,authenticating objects, and/or determining the health of objects.Further, the placement of where the OAMB-polyamides are located in theobjects is used as another layer of fingerprinting the objects foridentifying objects, tracking objects, authenticating objects, and/ordetermining the health of objects.

Methods of identifying objects, tracking objects, authenticatingobjects, and/or determining the health of objects may include (a)exposing the object comprising OAMB-polyamides to electromagneticradiation (e.g., for fluorophores preferably at a wavelength of 302 nmor less or 700 nm or greater); (b) sensing one or more spectra relatedto the electromagnetic radiation absorbed and/or reemitted (e.g., forfluorophores preferably the photoluminescence emitted between 302 nm to700 nm); and (c) comparing the spectra to the known spectra for theoptical absorbers used in said object or a portion thereof. Optionally,the location of where the spectra area is located on the object may becompared to the known location where the spectra area should be. Thecomparison(s) can be used for identifying and/or authenticating theobject. For tracking, the comparison(s) may be done and/or the detectedspectra and/or spectra area may be logged into a database along with thephysical location of the object. Further, the health of objects thatwear and/or crack can be ascertained. For example, a core portion of thearticle may comprise optical absorbers and an outer portion may coverthe core portion and not comprise the optical absorbers (or comprisedifferent optical absorbers). Then, when comparing spectra, theappearance of spectral features for the optical absorbers in the coremay indicate that the object is at or near the end of life.

By way of nonlimiting example, 3-D printing processes of the presentdisclosure may comprise: depositing particles comprising one or moreOAMB-polyamides of the present disclosure (and optionally one or moreother thermoplastic polymers and/or one or more compatibilizers) upon asurface in a specified shape, and once deposited, heating at least aportion of the particles to promote consolidation thereof and form aconsolidated body (object), such that the consolidated body has a voidpercentage of about 1% or less after being consolidated. For example,heating and consolidation of the thermoplastic polymer particles maytake place in a 3-D printing apparatus employing a laser, such thatheating and consolidation take place by selective laser sintering.

By way of nonlimiting example, 3-D printing processes of the presentdisclosure may comprise: extruding a filament comprising one or moreOAMB-polyamides of the present disclosure (and optionally one or moreother thermoplastic polymers and/or one or more compatibilizers) throughan orifice, wherein the filament becomes a polymer melt upon extrusion;depositing the polymer melt as a first layer on a platform; cooling thelayer; depositing an additional layer of the polymer melt on the firstlayer; cooling the additional layer; repeating depositing and coolingfor at least one additional layer to produce a 3-D shape.

Yet another nonlimiting example is a method comprising: extruding apolymer melt comprising one or more OAMB-polyamides of the presentdisclosure (and optionally one or more other thermoplastic polymersand/or one or more compatibilizers) through an orifice to produce afilm, a fiber (or a filament), particles, pellets, or the like.

Thermoplastic Polymer Particles and Methods of Making

The FIGURE is a flow chart of a nonlimiting example method 100 of thepresent disclosure. Thermoplastic polymer 102 (comprising one or moreOAMB-polyamides and optionally one or more other thermoplasticpolymers), carrier fluid 104, and optionally emulsion stabilizer 106 arecombined 108 to produce a mixture 110. The components 102, 104, and 106can be added in any order and include mixing and/or heating during theprocess of combining 108 the components 102, 104, and 106.

The mixture 110 is then processed 112 by applying sufficiently highshear to the mixture 110 at a temperature greater than the melting pointor softening temperature of the thermoplastic polymer 102 to form a meltemulsion 114. Because the temperature is above the melting point orsoftening temperature of the thermoplastic polymer 102, thethermoplastic polymer 102 becomes a polymer melt. The shear rate shouldbe sufficient enough to disperse the polymer melt in the carrier fluid104 as droplets (i.e., the polymer emulsion 114). Without being limitedby theory, it is believed that, all other factors being the same,increasing shear should decrease the size of the droplets of the polymermelt in the carrier fluid 104. However, at some point there may bediminishing returns on increasing shear and decreasing droplet size ormay be disruptions to the droplet contents that decrease the quality ofparticles produced therefrom.

The melt emulsion 114 inside and/or outside the mixing vessel is thencooled 116 to solidify the polymer droplets into thermoplastic polymerparticles (also referred to as solidified thermoplastic polymerparticles). The cooled mixture 118 can then be treated 120 to isolatethe thermoplastic polymer particles 122 from other components 124 (e.g.,the carrier fluid 104, excess emulsion stabilizer 106, and the like) andwash or otherwise purify the thermoplastic polymer particles 122. Thethermoplastic polymer particles 122 comprise the thermoplastic polymer102 and, when included, at least a portion of the emulsion stabilizer106 coating the outer surface of the thermoplastic polymer particles122. Emulsion stabilizers 106, or a portion thereof, may be deposited asa uniform coating on the thermoplastic polymer particles 122. In someinstances, which may be dependent upon non-limiting factors such as thetemperature (including cooling rate), the type of thermoplastic polymer102, and the types and sizes of emulsion stabilizers 106, thenanoparticles of emulsion stabilizers 106 may become at least partiallyembedded within the outer surface of thermoplastic polymer particles 122in the course of becoming associated therewith. Even without embedmenttaking place, at least the nanoparticles within emulsion stabilizers 106may remain robustly associated with thermoplastic polymer particles 122to facilitate their further use. In contrast, dry blending alreadyformed thermoplastic polymer particulates (e.g., formed by cryogenicgrinding or precipitation processes) with a flow aid like silicananoparticles does not result in a robust, uniform coating of the flowaid upon the thermoplastic polymer particulates.

Advantageously, carrier fluids and washing solvents of the systems andmethods described herein (e.g., method 100) can be recycled and reused.One skilled in the art will recognize any necessary cleaning of usedcarrier fluid and solvent necessary in the recycling process.

The thermoplastic polymer 102 and carrier fluid 104 should be chosensuch that at the various processing temperatures (e.g., from roomtemperature to process temperature) the thermoplastic polymer 102 andcarrier fluid 104 are immiscible. An additional factor that may beconsidered is the differences in (e.g., a difference or a ratio of)viscosity at process temperature between the molten polyamide 102 andthe carrier fluid 104. The differences in viscosity may affect dropletbreakup and particle size distribution. Without being limited by theory,it is believed that when the viscosities of the molten polyamide 102 andthe carrier fluid 104 are too similar, the circularity of the product asa whole may be reduced where the particles are more ovular and moreelongated structures are observed.

The thermoplastic polymers 102 comprises one or more OAMB-polyamides andoptionally one or more other thermoplastic polymers. Examples of otherthermoplastic polymers include, but are not limited to, polyamides,polyurethanes, polyethylenes, polypropylenes, polyacetals,polycarbonates, polybutylene terephthalate (PBT), polyethyleneterephthalate (PET), polyethylene naphthalate (PEN), polytrimethyleneterephthalate (PTT), polyhexamethylene terephthalate, polystyrenes,polyvinyl chlorides, polytetrafluoroethenes, polyesters (e.g.,polylactic acid), polyethers, polyether sulfones, polyetheretherketones, polyacrylates, polymethacrylates, polyimides, acrylonitrilebutadiene styrene (ABS), polyphenylene sulfides, vinyl polymers,polyarylene ethers, polyarylene sulfides, polysulfones, polyetherketones, polyamide-imides, polyetherimides, polyetheresters, copolymerscomprising a polyether block and a polyamide block (PEBA or polyetherblock amide), grafted or ungrafted thermoplastic polyolefins,functionalized or nonfunctionalized ethylene/vinyl monomer polymer,functionalized or nonfunctionalized ethylene/alkyl (meth)acrylates,functionalized or nonfunctionalized (meth)acrylic acid polymers,functionalized or nonfunctionalized ethylene/vinyl monomer/alkyl(meth)acrylate terpolymers, ethylene/vinyl monomer/carbonyl terpolymers,ethylene/alkyl (meth)acrylate/carbonyl terpolymers,methylmethacrylate-butadiene-styrene (MBS)-type core-shell polymers,polystyrene-block-polybutadiene-block-poly(methyl methacrylate) (SBM)block terpolymers, chlorinated or chlorosulphonated polyethylenes,polyvinylidene fluoride (PVDF), phenolic resins, poly(ethylene/vinylacetate)s, polybutadienes, polyisoprenes, styrenic block copolymers,polyacrylonitriles, silicones, and the like, and any combinationthereof. Copolymers comprising one or more of the foregoing may also beused in the methods and systems of the present disclosure.

The other thermoplastic polymers in the compositions and methods of thepresent disclosure may be elastomeric or non-elastomeric. Some of theforegoing examples of other thermoplastic polymers may be elastomeric ornon-elastomeric depending on the exact composition of the polymer. Forexample, polyethylene that is a copolymer of ethylene and propylene maybe elastomeric or not depending on the amount of propylene in thepolymer.

Thermoplastic elastomers generally fall within one of six classes:styrenic block copolymers, thermoplastic polyolefin elastomers,thermoplastic vulcanizates (also referred to as elastomeric alloys),thermoplastic polyurethanes, thermoplastic copolyesters, andthermoplastic polyamides (typically block copolymers comprisingpolyamide). Examples of thermoplastic elastomers can be found in the“Handbook of Thermoplastic Elastomers,” 2nd ed., B. M. Walker and C. P.Rader, eds., Van Nostrand Reinhold, New York, 1988. Examples ofthermoplastic elastomers include, but are not limited to, elastomericpolyamides, polyurethanes, copolymers comprising a polyether block and apolyamide block (PEBA or polyether block amide), methylmethacrylate-butadiene-styrene (MBS)-type core-shell polymers,polystyrene-block-polybutadiene-block-poly(methyl methacrylate) (SBM)block terpolymers, polybutadienes, polyisoprenes, styrenic blockcopolymers, and polyacrylonitriles), silicones, and the like.Elastomeric styrenic block copolymers may include at least one blockselected from the group of: isoprene, isobutylene, butylene,ethylene/butylene, ethylene-propylene, and ethylene-ethylene/propylene.More specific elastomeric styrenic block copolymer examples include, butare not limited to, poly(styrene-ethylene/butylene), poly(styrene-ethylene/butyl ene-styrene), poly(styrene-ethylene/propylene),styrene-ethylene/propylene-styrene),poly(styrene-ethylene/propylene-styrene-ethyl ene-propyl ene),poly(styrene-butadiene-styrene), poly(styrene-butylene-butadiene-styrene), and the like, and any combination thereof.

Examples of polyamides include, but are not limited to, polycaproamide,poly(hexamethylene succinamide), polyhexamethylene adipamide,polypentamethylene adipamide, polyhexamethylene sebacamide,polyundecamide, polydodecamide, polyhexamethylene terephthalamide, nylon10,10, nylon 10,12, nylon 10,14, nylon 10,18, nylon 6,18, nylon 6,12,nylon 6,14, nylon 12,12, a semi-aromatic polyamide, an aromaticpolyamide, any copolymer thereof, and any combination thereof.Copolyamides may also be used. Examples of copolyamides include, but arenot limited to, PA 11/10.10, PA 6/11, PA 6.6/6, PA 11/12, PA10.10/10.12, PA 10.10/10.14, PA 11/10.36, PA 11/6.36, PA 10.10/10.36,and the like, and any combination thereof. Examples of polyamideelastomers include, but are not limited to, polyesteramide,polyetheresteramide, polycarbonate-esteramide, and polyether-block-amideelastomers.

Examples of polyurethanes include, but are not limited to, polyetherpolyurethanes, polyester polyurethanes, mixed polyether and polyesterpolyurethanes, and the like, and any combination thereof. Examples ofthermoplastic polyurethanes include, but are not limited to,poly[4,4′-methylenebis(phenylisocyanate)-alt-1,4-butanediol/di(propyleneglycol)/polycaprolactone], ELASTOLLAN® 1190A (a polyether polyurethaneelastomer, available from BASF), ELASTOLLAN® 1190A10 (a polyetherpolyurethane elastomer, available from BASF), and the like, and anycombination thereof.

Compatibilizers may optionally be used to improve the blendingefficiency and efficacy OAMB-polyamides with one or more thermoplasticpolymers. Examples of polymer compatibilizers include, but not limitedto, PROPOLDER™ MPP2020 20 (polypropylene, available from PolygroupInc.), PROPOLDER™ MPP2040 40 (polypropylene, available from PolygroupInc.), NOVACOM™ HFS2100 (maleic anhydride functionalized high densitypolyethylene polymer, available from Polygroup Inc.), KEN-REACT™ CAPS™L™ 12/L (organometallic coupling agent, available from KenrichPetrochemicals), KEN-REACT™ CAPOW™ L™ 12/H (organometallic couplingagent, available from Kenrich Petrochemicals), KEN-REACT™ LICA™ 12(organometallic coupling agent, available from Kenrich Petrochemicals),KEN-REACT™ CAPS™ KPR™ 12/LV (organometallic coupling agent, availablefrom Kenrich Petrochemicals), KEN-REACT™ CAPOW™ KPR™ 12/H(organometallic coupling agent, available from Kenrich Petrochemicals),KEN-REACT™ titanates & zirconates (organometallic coupling agent,available from Kenrich Petrochemicals), VISTAMAXX™ (ethylene-propylenecopolymers, available from ExxonMobil), SANTOPRENE™ (thermoplasticvulcanizate of ethylene-propylene-diene rubber and polypropylene,available from ExxonMobil), VISTALON™ (ethylene-propylene-diene rubber,available from ExxonMobil), EXACT™ (plastomers, available fromExxonMobil) EXXELOR™ (polymer resin, available from ExxonMobil),FUSABOND™ M603 (random ethylene copolymer, available from Dow),FUSABOND™ E226 (anhydride modified polyethylene, available from Dow),BYNEL™ 41E710 (coextrudable adhesive resin, available from Dow), SURLYN™1650 (ionomer resin, available from Dow), FUSABOND™ P353 (a chemicallymodified polypropylene copolymer, available from Dow), ELVALOY™ PTW(ethylene terpolymer, available from Dow), ELVALOY™ 3427AC (a copolymerof ethylene and butyl acrylate, available from Dow), LOTADER™ AX8840(ethylene acrylate-based terpolymer, available from Arkema), LOTADER™3210 (ethylene acrylate-based terpolymer, available from Arkema),LOTADER™ 3410 (ethylene acrylate-based terpolymer, available fromArkema), LOTADER™ 3430 (ethylene acrylate-based terpolymer, availablefrom Arkema), LOTADER™ 4700 (ethylene acrylate-based terpolymer,available from Arkema), LOTADER™ AX8900 (ethylene acrylate-basedterpolymer, available from Arkema), LOTADER™ 4720 (ethyleneacrylate-based terpolymer, available from Arkema), BAXXODUR™ EC 301(amine for epoxy, available from BASF), BAXXODUR™ EC 311 (amine forepoxy, available from BASF), BAXXODUR™ EC 303 (amine for epoxy,available from BASF), BAXXODUR™ EC 280 (amine for epoxy, available fromBASF), BAXXODUR™ EC 201 (amine for epoxy, available from BASF),BAXXODUR™ EC 130 (amine for epoxy, available from BASF), BAXXODUR™ EC110 (amine for epoxy, available from BASF), styrenics, polypropylene,polyamides, polycarbonate, EASTMAN™ G-3003 (a maleic anhydride graftedpolypropylene, available from Eastman), RETAIN™ (polymer modifieravailable from Dow), AMPLIFY TY™ (maleic anhydride grafted polymer,available from Dow), INTUNE™ (olefin block copolymer, available fromDow), and the like, and any combination thereof.

The thermoplastic polymers 102 (comprising one or more OAMB-polyamidesand optionally one or more other thermoplastic polymers) may have amelting point or softening temperature of about 50° C. to about 450° C.(or about 50° C. to about 125° C., or about 100° C. to about 175° C., orabout 150° C. to about 280° C., or about 200° C. to about 350° C., orabout 300° C. to about 450° C.).

The thermoplastic polymers 102 may have a glass transition temperature(ASTM E1356-08(2014) with 10° C./min. ramping and cooling rates) ofabout −50° C. to about 400° C. (or about −50° C. to about 0° C., orabout −25° C. to about 50° C., or about 0° C. to about 150° C., or about100° C. to about 250° C., or about 150° C. to about 300° C., or about200° C. to about 400° C.).

The thermoplastic polymers 102 may optionally comprise an additive.Typically, the additive would be present before addition of thethermoplastic polymers 102 to the mixture 110. Therefore, in thethermoplastic polymer melt droplets and resultant thermoplastic polymerparticles, the additive is dispersed throughout the thermoplasticpolymer. Accordingly, for clarity, this additive is referred to hereinas an “internal additive.” The internal additive may be blended with thethermoplastic polymer just prior to making the mixture 110 or well inadvance.

When describing component amounts in the compositions described herein(e.g., the mixture 110 and thermoplastic polymer particles 122), aweight percent based on the thermoplastic polymer 102 not inclusive ofthe internal additive. For example, a composition comprising 1 wt % ofemulsion stabilizer by weight of 100 g of a thermoplastic polymer 102comprising 10 wt % internal additive and 90 wt % thermoplastic polymeris a composition comprising 0.9 g of emulsion stabilizer, 90 g ofthermoplastic polymer, and 10 g of internal additive.

The internal additive may be present in the thermoplastic polymer 102 atabout 0.1 wt % to about 60 wt % (or about 0.1 wt % to about 5 wt %, orabout 1 wt % to about 10 wt %, or about 5 wt % to about 20 wt %, orabout 10 wt % to about 30 wt %, or about 25 wt % to about 50 wt %, orabout 40 wt % to about 60 wt %) of the thermoplastic polymer 102. Forexample, the thermoplastic polymer 102 may comprise about 70 wt % toabout 85 wt % of a thermoplastic polymer and about 15 wt % to about 30wt % of an internal additive like glass fiber or carbon fiber.

Examples of internal additives include, but are not limited to, fillers,strengtheners, pigments, pH regulators, and the like, and combinationsthereof. Examples of fillers include, but are not limited to, glassfibers, glass particles, mineral fibers, carbon fiber, oxide particles(e.g., titanium dioxide and zirconium dioxide), metal particles (e.g.,aluminum powder), and the like, and any combination thereof. Examples ofpigments include, but are not limited to, organic pigments, inorganicpigments, carbon black, and the like, and any combination thereof.

The thermoplastic polymer 102 may be present in the mixture 110 at about5 wt % to about 60 wt % (or about 5 wt % to about 25 wt %, or about 10wt % to about 30 wt %, or about 20 wt % to about 45 wt %, or about 25 wt% to about 50 wt %, or about 40 wt % to about 60 wt %) of thethermoplastic polymer 102 and carrier fluid 104 combined.

Suitable carrier fluids 104 have a viscosity at 25° C. of about 1,000cSt to about 150,000 cSt (or about 1,000 cSt to about 60,000 cSt, orabout 40,000 cSt to about 100,000 cSt, or about 75,000 cSt to about150,000 cSt).

Examples of carrier fluids 104 include, but are not limited to, siliconeoil, fluorinated silicone oils, perfluorinated silicone oils,polyethylene glycols, alkyl-terminal polyethylene glycols (e.g., C1-C4terminal alkyl groups like tetraethylene glycol dimethyl ether (TDG)),paraffins, liquid petroleum jelly, vison oils, turtle oils, soya beanoils, perhydrosqualene, sweet almond oils, calophyllum oils, palm oils,parleam oils, grapeseed oils, sesame oils, maize oils, rapeseed oils,sunflower oils, cottonseed oils, apricot oils, castor oils, avocadooils, jojoba oils, olive oils, cereal germ oils, esters of lanolic acid,esters of oleic acid, esters of lauric acid, esters of stearic acid,fatty esters, higher fatty acids, fatty alcohols, polysiloxanes modifiedwith fatty acids, polysiloxanes modified with fatty alcohols,polysiloxanes modified with polyoxy alkylenes, and the like, and anycombination thereof. Examples of silicone oils include, but are notlimited to, polydimethylsiloxane, methylphenylpolysiloxane, an alkylmodified polydimethylsiloxane, an alkyl modifiedmethylphenylpolysiloxane, an amino modified polydimethylsiloxane, anamino modified methylphenylpolysiloxane, a fluorine modifiedpolydimethylsiloxane, a fluorine modified methylphenylpolysiloxane, apolyether modified polydimethylsiloxane, a polyether modifiedmethylphenylpolysiloxane, and the like, and any combination thereof.When the carrier fluid 104 comprises two or more of the foregoing, thecarrier fluid 104 may have one or more phases. For example,polysiloxanes modified with fatty acids and polysiloxanes modified withfatty alcohols (preferably with similar chain lengths for the fattyacids and fatty alcohols) may form a single-phase carrier fluid 104. Inanother example, a carrier fluid 104 comprising a silicone oil and analkyl-terminal polyethylene glycol may form a two-phase carrier fluid104.

The carrier fluid 104 may be present in the mixture 110 at about 40 wt %to about 95 wt % (or about 75 wt % to about 95 wt %, or about 70 wt % toabout 90 wt %, or about 55 wt % to about 80 wt %, or about 50 wt % toabout 75 wt %, or about 40 wt % to about 60 wt %) of the thermoplasticpolymer 102 and carrier fluid 104 combined.

In some instances, the carrier fluid 104 may have a density of about 0.6g/cm³ to about 1.5 g/cm³, and the thermoplastic polymer 102 has adensity of about 0.7 g/cm³ to about 1.7 g/cm³, wherein the thermoplasticpolymer has a density similar, lower, or higher than the density of thecarrier fluid.

The emulsion stabilizers used in the methods and compositions of thepresent disclosure may comprise nanoparticles (e.g. oxide nanoparticles,carbon black, polymer nanoparticles, and combinations thereof),surfactants, and the like, and any combination thereof.

Oxide nanoparticles may be metal oxide nanoparticles, non-metal oxidenanoparticles, or mixtures thereof. Examples of oxide nanoparticlesinclude, but are not limited to, silica, titania, zirconia, alumina,iron oxide, copper oxide, tin oxide, boron oxide, cerium oxide, thalliumoxide, tungsten oxide, and the like, and any combination thereof. Mixedmetal oxides and/or non-metal oxides, like aluminosilicates,borosilicates, and aluminoborosilicates, are also inclusive in the termmetal oxide. The oxide nanoparticles may by hydrophilic or hydrophobic,which may be native to the particle or a result of surface treatment ofthe particle. For example, a silica nanoparticle having a hydrophobicsurface treatment, like dimethyl silyl, trimethyl silyl, and the like,may be used in methods and compositions of the present disclosure.Additionally, silica with functional surface treatments likemethacrylate functionalities may be used in methods and compositions ofthe present disclosure. Unfunctionalized oxide nanoparticles may also besuitable for use as well.

Commercially available examples of silica nanoparticles include, but arenot limited to, AEROSIL® particles available from Evonik (e.g., AEROSIL®R812S (about 7 nm average diameter silica nanoparticles having ahydrophobically modified surface and a BET surface area of 260±30 m²/g),AEROSIL® RX50 (about 40 nm average diameter silica nanoparticles havinga hydrophobically modified surface and a BET surface area of 35±10m²/g), AEROSIL® 380 (silica nanoparticles having a hydrophilicallymodified surface and a BET surface area of 380±30 m²/g), and the like,and any combination thereof.

Carbon black is another type of nanoparticle that may be present as anemulsion stabilizer in the compositions and methods disclosed herein.Various grades of carbon black will be familiar to one having ordinaryskill in the art, any of which may be used herein. Other nanoparticlescapable of absorbing infrared radiation may be used similarly.

Polymer nanoparticles are another type of nanoparticle that may bepresent as an emulsion stabilizer in the disclosure herein. Suitablepolymer nanoparticles may include one or more polymers that arethermosetting and/or crosslinked, such that they do not melt whenprocessed by melt emulsification according to the disclosure herein.High molecular weight thermoplastic polymers having high melting ordecomposition points may similarly comprise suitable polymernanoparticle emulsion stabilizers.

The nanoparticles may have an average diameter (D50 based on volume) ofabout 1 nm to about 500 nm (or about 10 nm to about 150 nm, or about 25nm to about 100 nm, or about 100 nm to about 250 nm, or about 250 nm toabout 500 nm).

The nanoparticles may have a BET surface area of about 10 m²/g to about500 m²/g (or about 10 m²/g to about 150 m²/g, or about 25 m²/g to about100 m²/g, or about 100 m²/g to about 250 m²/g, or about 250 m²/g toabout 500 m²/g).

Nanoparticles may be included in the mixture 110 at a concentration ofabout 0.01 wt % to about 10 wt % (or about 0.01 wt % to about 1 wt %, orabout 0.1 wt % to about 3 wt %, or about 1 wt % to about 5 wt %, orabout 5 wt % to about 10 wt %) based on the weight of the thermoplasticpolymer 102.

Surfactants may be anionic, cationic, nonionic, or zwitterionic.Examples of surfactants include, but are not limited to, sodium dodecylsulfate, sorbitan oleates,poly[dimethylsiloxane-co-[3-(2-(2-hydroxyethoxy)ethoxy)propylmethylsiloxane],docusate sodium (sodium1,4-bis(2-ethylhexoxy)-1,4-dioxobutane-2-sulfonate), and the like, andany combination thereof. Commercially available examples of surfactantsinclude, but are not limited to, CALFAX® DB-45 (sodium dodecyl diphenyloxide disulfonate, available from Pilot Chemicals), SPAN® 80 (sorbitanmaleate non-ionic surfactant), MERPOL® surfactants (available fromStepan Company), TERGITOL™ TMN-6 (a water-soluble, nonionic surfactant,available from DOW), TRITON™ X-100 (octyl phenol ethoxylate, availablefrom SigmaAldrich), IGEPAL® CA-520 (polyoxyethylene (5) isooctylphenylether, available from SigmaAldrich), BRIJ® S10 (polyethylene glycoloctadecyl ether, available from SigmaAldrich), and the like, and anycombination thereof.

Surfactants may be included in the mixture 110 at a concentration ofabout 0.01 wt % to about 10 wt % (or about 0.01 wt % to about 1 wt %, orabout 0.5 wt % to about 2 wt %, or about 1 wt % to about 3 wt %, orabout 2 wt % to about 5 wt %, or about 5 wt % to about 10 wt %) based onthe weight of the polyamide 102. Alternatively, the mixture 110 maycomprise no (or be absent of) surfactant.

A weight ratio of nanoparticles to surfactant may be about 1:10 to about10:1 (or about 1:10 to about 1:1, or about 1:5 to about 5:1, or about1:1 to about 10:1).

As described above, the components 102, 104, and 106 can be added in anyorder and include mixing and/or heating during the process of combining108 the components 102, 104, and 106. For example, the emulsionstabilizer 106 may first be dispersed in the carrier fluid 104,optionally with heating said dispersion, before adding the thermoplasticpolymer 102. In another nonlimiting example, the thermoplastic polymer102 may be heated to produce a polymer melt to which the carrier fluid104 and emulsion stabilizer 106 are added together or in either order.In yet another nonlimiting example, the thermoplastic polymer 102 andcarrier fluid 104 can be mixed at a temperature greater than the meltingpoint or softening temperature of the thermoplastic polymer 102 and at ashear rate sufficient enough to disperse the thermoplastic polymer meltin the carrier fluid 104. Then, the emulsion stabilizer 106 can be addedto form the mixture 110 and maintained at suitable process conditionsfor a set period of time.

Combining 108 the components 102, 104, and 106 in any combination canoccur in a mixing apparatus used for the processing 112 and/or anothersuitable vessel. By way of nonlimiting example, the thermoplasticpolymer 102 may be heated to a temperature greater than the meltingpoint or softening temperature of the thermoplastic polymer 102 in themixing apparatus used for the processing 112, and the emulsionstabilizer 106 may be dispersed in the carrier fluid 104 in anothervessel. Then, said dispersion may be added to the melt of thethermoplastic polymer 102 in the mixing apparatus used for theprocessing 112.

The mixing apparatuses used for the processing 112 to produce the meltemulsion 114 should be capable of maintaining the melt emulsion 114 at atemperature greater than the melting point or softening temperature ofthe thermoplastic polymer 102 and applying a shear rate sufficient todisperse the polymer melt in the carrier fluid 104 as droplets.

Examples of mixing apparatuses used for the processing 112 to producethe melt emulsion 114 include, but are not limited to, extruders (e.g.,continuous extruders, batch extruders, and the like), stirred reactors,blenders, reactors with inline homogenizer systems, and the like, andapparatuses derived therefrom.

Processing 112 and forming the melt emulsion 114 at suitable processconditions (e.g., temperature, shear rate, and the like) for a setperiod of time.

The temperature of processing 112 and forming the melt emulsion 114should be a temperature greater than the melting point or softeningtemperature of the thermoplastic polymer 102 and less than thedecomposition temperature of any components 102, 104, and 106 in themixture 110. For example, the temperature of processing 112 and formingthe melt emulsion 114 may be about 1° C. to about 50° C. (or about 1° C.to about 25° C., or about 5° C. to about 30° C., or about 20° C. toabout 50° C.) greater than the melting point or softening temperature ofthe thermoplastic polymer 102 provided the temperature of processing 112and forming the melt emulsion 114 is less than the decompositiontemperature of any components 102, 104, and 106 in the mixture 110.

The shear rate of processing 112 and forming the melt emulsion 114should be sufficiently high to disperse the polymer melt in the carrierfluid 104 as droplets. Said droplets should comprise droplets having adiameter of about 1,000 μm or less (or about 1 μm to about 1,000 μm, orabout 1 μm to about 50 μm, or about 10 μm to about 100 μm, or about 10μm to about 250 μm, or about 50 μm to about 500 μm, or about 250 μm toabout 750 μm, or about 500 μm to about 1,000 μm).

The time for maintaining said temperature and shear rate for processing112 and forming the melt emulsion 114 may be 10 seconds to 18 hours orlonger (or 10 seconds to 30 minutes, or 5 minutes to 1 hour, or 15minutes to 2 hours, or 1 hour to 6 hours, or 3 hours to 18 hours).Without being limited by theory, it is believed that a steady state ofdroplet sizes will be reached at which point processing 112 can bestopped. That time may depend on, among other things, the temperature,shear rate, thermoplastic polymer 102 composition, the carrier fluid 104composition, and the emulsion stabilizer 106 composition.

The melt emulsion 114 may then be cooled 116. Cooling 116 can be slow(e.g., allowing the melt emulsion to cool under ambient conditions) tofast (e.g., quenching). For example, the rate of cooling may range fromabout 10° C./hour to about 100° C./second to almost instantaneous withquenching (for example in dry ice) (or about 10° C./hour to about 60°C./hour, or about 0.5° C./minute to about 20° C./minute, or about 1°C./minute to about 5° C./minute, or about 10° C./minute to about 60°C./minute, or about 0.5° C./second to about 10° C./second, or about 10°C./second to about 100° C./second).

During cooling, little to no shear may be applied to the melt emulsion114. In some instances, the shear applied during heating may be appliedduring cooling.

The cooled mixture 118 resulting from cooling 116 the melt emulsion 114comprises solidified thermoplastic polymer particles 122 (or simplythermoplastic polymer particles) and other components 124 (e.g., thecarrier fluid 104, excess emulsion stabilizer 106, and the like). Thethermoplastic polymer particles may be dispersed in the carrier fluid orsettled in the carrier fluid.

The cooled mixture 118 may then be treated 120 to the separatethermoplastic polymer particles 122 (or simply thermoplastic polymerparticles 122) from the other components 124. Suitable treatmentsinclude, but are not limited to, washing, filtering, centrifuging,decanting, and the like, and any combination thereof.

Solvents used for washing the thermoplastic polymer particles 122 shouldgenerally be (a) miscible with the carrier fluid 104 and (b) nonreactive(e.g., non-swelling and non-dissolving) with the thermoplastic polymer102. The choice of solvent will depend on, among other things, thecomposition of the carrier fluid and the composition of thethermoplastic polymer 102.

Examples of solvents include, but are not limited to, hydrocarbonsolvents (e.g., pentane, hexane, heptane, octane, cyclohexane,cyclopentane, decane, dodecane, tridecane, and tetradecane), aromatichydrocarbon solvents (e.g., benzene, toluene, xylene, 2-methylnaphthalene, and cresol), ether solvents (e.g., diethyl ether,tetrahydrofuran, diisopropyl ether, and dioxane), ketone solvents (e.g.,acetone and methyl ethyl ketone), alcohol solvents (e.g., methanol,ethanol, isopropanol, and n-propanol), ester solvents (e.g., ethylacetate, methyl acetate, butyl acetate, butyl propionate, and butylbutyrate), halogenated solvents (e.g., chloroform, bromoform,1,2-dichloromethane, 1,2-dichloroethane, carbon tetrachloride,chlorobenzene, and hexafluoroisopropanol), water, and the like, and anycombination thereof.

Solvent may be removed from the thermoplastic polymer particles 122 bydrying using an appropriate method such as air drying, heat drying,reduced pressure drying, freeze drying, or a hybrid thereof. The heatingmay be performed preferably at a temperature lower than the glasstransition point of the thermoplastic polymer (e.g., about 50° C. toabout 150° C.).

The thermoplastic polymer particles 122 after separation from the othercomponents 124 may optionally be further classified to produce purifiedthermoplastic polymer particles 128. For example, to narrow the particlesize distribution (or reduce the diameter span), the thermoplasticpolymer particles 122 can be passed through a sieve having a pore sizeof about 10 μm to about 250 μm (or about 10 μm to about 100 μm, or about50 μm to about 200 μm, or about 150 μm to about 250 μm).

In another example of purification technique, the thermoplastic polymerparticles 122 may be washed with water to remove surfactant whilemaintaining substantially all of the nanoparticles associated with thesurface of the thermoplastic polymer particles 122. In yet anotherexample of purification technique, the thermoplastic polymer particles122 may be blended with additives to achieve a desired final product.For clarity, because such additives are blended with the thermoplasticparticles 122 or other particles resultant from the methods describedherein after the particles are solidified, such additives are referredto herein as “external additives.” Examples of external additivesinclude flow aids, other polymer particles, fillers, and the like, andany combination thereof.

In some instances, a surfactant used in making the thermoplastic polymerparticles 122 may be unwanted in downstream applications. Accordingly,yet another example of purification technique may include at leastsubstantial removal of the surfactant from the thermoplastic polymerparticles 122 (e.g., by washing and/or pyrolysis).

The thermoplastic polymer particles 122 and/or purified thermoplasticpolymer particles 128 (referred to as particles 122/128) may becharacterized by composition, physical structure, and the like.

As described above, the emulsion stabilizers are at the interfacebetween the polymer melt and the carrier fluid. As a result, when themixture is cooled, the emulsion stabilizers remain at, or in thevicinity of, said interface. Therefore, the structure of the particles122/128, in general, includes emulsion stabilizers (a) dispersed on anouter surface of the particles 122/128 and/or (b) embedded in an outerportion (e.g., outer 1 vol %) of the particles 122/128.

Further, where voids form inside the polymer melt droplets, emulsionstabilizers 106 should generally be at (and/or embedded in) theinterface between the interior of the void and the thermoplasticpolymer. The voids generally do not contain the thermoplastic polymer.Rather, the voids may contain, for example, carrier fluid, air, or bevoid. The particles 122/128 may comprise carrier fluid at about 5 wt %or less (or about 0.001 wt % to about 5 wt %, or about 0.001 wt % toabout 0.1 wt %, or about 0.01 wt % to about 0.5 wt %, or about 0.1 wt %to about 2 wt %, or about 1 wt % to about 5 wt %) of the particles122/128.

The thermoplastic polymer 102 may be present in the particles 122/128 atabout 90 wt % to about 99.5 wt % (or about 90 wt % to about 95 wt %, orabout 92 wt % to about 97 wt %, or about 95 wt % to about 99.5 wt %) ofthe particles 122/128.

When included, the emulsion stabilizers 106 may be present in theparticles 122/128 at about 10 wt % or less (or about 0.01 wt % to about10 wt %, or about 0.01 wt % to about 1 wt %, or about 0.5 wt % to about5 wt %, or about 3 wt % to about 7 wt %, or about 5 wt % to about 10 wt%) of the particles 122/128. When purified to at least substantiallyremove surfactant or another emulsion stabilizer, the emulsionstabilizers 106 may be present in the particles 128 at less than 0.01 wt% (or 0 wt % to about 0.01 wt %, or 0 wt % to 0.001 wt %).

Upon forming thermoplastic particulates according to the disclosureherein, at least a portion of the nanoparticles, such as silicananoparticles, may be disposed as a coating upon the outer surface ofthe thermoplastic particulates. At least a portion of the surfactant, ifused, may be associated with the outer surface as well. The coating maybe disposed substantially uniformly upon the outer surface. As usedherein with respect to a coating, the term “substantially uniform”refers to even coating thickness in surface locations covered by thecoating composition (e.g., nanoparticles and/or surfactant),particularly the entirety of the outer surface. The emulsion stabilizers106 may form a coating that covers at least 5% (or about 5% to about100%, or about 5% to about 25%, or about 20% to about 50%, or about 40%to about 70%, or about 50% to about 80%, or about 60% to about 90%, orabout 70% to about 100%) of the surface area of the particles 122/128.When purified to at least substantially remove surfactant or anotheremulsion stabilizer, the emulsion stabilizers 106 may be present in theparticles 128 at less than 25% (or 0% to about 25%, or about 0.1% toabout 5%, or about 0.1% to about 1%, or about 1% to about 5%, or about1% to about 10%, or about 5% to about 15%, or about 10% to about 25%) ofthe surface area of the particles 128. The coverage of the emulsionstabilizers 106 on an outer surface of the particles 122/128 may bedetermined using image analysis of the scanning electron microscopeimages (SEM micrographs). The emulsion stabilizers 106 may form acoating that covers at least 5% (or about 5% to about 100%, or about 5%to about 25%, or about 20% to about 50%, or about 40% to about 70%, orabout 50% to about 80%, or about 60% to about 90%, or about 70% to about100%) of the surface area of the particles 122/128. When purified to atleast substantially remove surfactant or another emulsion stabilizer,the emulsion stabilizers 106 may be present in the particles 128 at lessthan 25% (or 0% to about 25%, or about 0.1% to about 5%, or about 0.1%to about 1%, or about 1% to about 5%, or about 1% to about 10%, or about5% to about 15%, or about 10% to about 25%) of the surface area of theparticles 128. The coverage of the emulsion stabilizers 106 on an outersurface of the particles 122/128 may be determined using image analysisof the SEM micrographs.

The particles 122/128 may have a D10 of about 0.1 μm to about 125 μm (orabout 0.1 μm to about 5 μm, about 1 μm to about 10 μm, about 5 μm toabout 30 μm, or about 1 μm to about 25 μm, or about 25 μm to about 75μm, or about 50 μm to about 85 μm, or about 75 μm to about 125 μm), aD50 of about 0.5 μm to about 200 μm (or about 0.5 μm to about 10 μm, orabout 5 μm to about 50 μm, or about 30 μm to about 100 μm, or about 30μm to about 70 μm, or about 25 μm to about 50 μm, or about 50 μm toabout 100 μm, or about 75 μm to about 150 μm, or about 100 μm to about200 μm), and a D90 of about 3 μm to about 300 μm (or about 3 μm to about15 μm, or about 10 μm to about 50 μm, or about 25 μm to about 75 μm, orabout 70 μm to about 200 μm, or about 60 μm to about 150 μm, or about150 μm to about 300 μm), wherein D10<D50<D90. The particles 122/128 mayalso have a diameter span of about 0.4 to about 3 (or about 0.6 to about2, or about 0.4 to about 1.5, or about 1 to about 3). Withoutlimitation, diameter span values of 1.0 or greater are considered broad,and diameter span values of 0.75 or less are considered narrow. Forexample, the particles 122/128 may have a D10 of about 5 μm to about 30μm, a D50 of about 30 μm to about 100 μm, and a D90 of about 70 μm toabout 120 μm, wherein D10<D50<D90.

The particles 122/128 may also have a diameter span of about 0.4 toabout 3 (or about 0.6 to about 2, or about 0.4 to about 1.5, or about 1to about 3).

In a first nonlimiting example, the particles 122/128 may have a D10 ofabout 0.5 μm to about 5 μm, a D50 of about 0.5 μm to about 10 μm, and aD90 of about 3 μm to about 15 μm, wherein D10<D50<D90.

In a second nonlimiting example, the particles 122/128 may have a D10 ofabout 1 μm to about 50 μm, a D50 of about 25 μm to about 100 μm, and aD90 of about 60 μm to about 300 μm, wherein D10<D50<D90.

In a third nonlimiting example, the particles 122/128 may have a D10 ofabout 5 μm to about 30 μm, a D50 of about 30 μm to about 70 μm, and aD90 of about 70 μm to about 120 pin, wherein D10<D50<D90. Said particles122/128 may have a diameter span of about 1.0 to about 2.5.

In a fourth nonlimiting example, the particles 122/128 may have a D10 ofabout 25 μm to about 60 μm, a D50 of about 60 μm to about 110 μm, and aD90 of about 110 μm to about 175 μm, wherein D10<D50<D90. Said particles122/128 may have a diameter span of about 0.6 to about 1.5.

In a fifth nonlimiting example, the particles 122/128 may have a D10 ofabout 75 μm to about 125 μm, a D50 of about 100 μm to about 200 μm, anda D90 of about 125 μm to about 300 μm, wherein D10<D50<D90. Saidparticles 122/128 may have a diameter span of about 0.2 to about 1.2.

The particles 122/128 may have a circularity of about 0.7 or greater (orabout 0.90 to about 1.0, or about 0.93 to about 0.99, or about 0.95 toabout 0.99, or about 0.97 to about 0.99, or about 0.98 to 1.0).

The particles 122/128 may have an angle of repose of about 25° to about45° (or about 25° to about 35°, or about 30° to about 40°, or about 35°to about 45°).

The particles 122/128 may have a Hausner ratio of about 1.0 to about 1.5(or about 1.0 to about 1.2, or about 1.1 to about 1.3, or about 1.2 toabout 1.35, or about 1.3 to about 1.5).

The particles 122/128 may have a bulk density of about 0.3 g/cm³ toabout 0.8 g/cm³ (or about 0.3 g/cm³ to about 0.6 g/cm³, or about 0.4g/cm³ to about 0.7 g/cm³, or about 0.5 g/cm³ to about 0.6 g/cm³, orabout 0.5 g/cm³ to about 0.8 g/cm³).

Depending on the temperature and shear rate of processing 112 and thecomposition and relative concentrations of the components 102, 104, and106, different shapes of the structures that compose the particles122/128 have been observed. Typically, the particles 122/128 comprisesubstantially of spherical particles (having a circularity of about 0.97or greater). However, other structures that included disc and elongatedstructures have been observed in the particles 122/128. Therefore, theparticles 122/128 may comprise one or more of: (a) substantiallyspherical particles having a circularity of 0.97 or greater, (b) discstructures having an aspect ratio of about 2 to about 10, and (c)elongated structures having an aspect ratio of 10 or greater. Each ofthe (a), (b), and (c) structures have emulsion stabilizers dispersed onan outer surface of the (a), (b), and (c) structures and/or embedded inan outer portion of the (a), (b), and (c) structures. At least some ofthe (a), (b), and (c) structures may be agglomerated. For example, the(c) elongated structures may be laying on the surface of the (a)substantially spherical particles.

The particles 122/128 may have a sintering window that is within 10° C.,preferably within 5° C., of the sintering window of the thermoplasticpolymer 102 (comprising one or more OAMB-polyamides and optionally oneor more other thermoplastic polymers).

Applications of OAMB-Polyamide Particles

The OAMB-polyamide particles described herein may be used to produce avariety of objects (or articles). The OAMB-polyamides described hereinmay be used alone or in combination with other particles comprisingother thermoplastic polymers (e.g., polyamides without an opticalabsorber and/or other thermoplastic polymers). Examples of thermoplasticpolymers that may be used in such other particles include, but are notlimited to, polyamides, polyurethanes, polyethylenes, polypropylenes,polyacetals, polycarbonates, polybutylene terephthalate (PBT),polyethylene terephthalate (PET), polyethylene naphthalate (PEN),polytrimethylene terephthalate (PTT), polyhexamethylene terephthalate,polystyrenes, polyvinyl chlorides, polytetrafluoroethenes, polyesters(e.g., polylactic acid), polyethers, polyether sulfones, polyetheretherketones, polyacrylates, polymethacrylates, polyimides, acrylonitrilebutadiene styrene (ABS), polyphenylene sulfides, vinyl polymers,polyarylene ethers, polyarylene sulfides, polysulfones, polyetherketones, polyamide-imides, polyetherimides, polyetheresters, copolymerscomprising a polyether block and a polyamide block (PEBA or polyetherblock amide), grafted or ungrafted thermoplastic polyolefins,functionalized or nonfunctionalized ethylene/vinyl monomer polymer,functionalized or nonfunctionalized ethylene/alkyl (meth)acrylates,functionalized or nonfunctionalized (meth)acrylic acid polymers,functionalized or nonfunctionalized ethylene/vinyl monomer/alkyl(meth)acrylate terpolymers, ethylene/vinyl monomer/carbonyl terpolymers,ethylene/alkyl (meth)acrylate/carbonyl terpolymers,methylmethacrylate-butadiene-styrene (MBS)-type core-shell polymers,polystyrene-block-polybutadiene-block-poly(methyl methacrylate) (SBM)block terpolymers, chlorinated or chlorosulphonated polyethylenes,polyvinylidene fluoride (PVDF), phenolic resins, poly(ethylene/vinylacetate)s, polybutadienes, polyisoprenes, styrenic block copolymers,polyacrylonitriles, silicones, and the like, and any combinationthereof. Copolymers comprising one or more of the foregoing may also beused in the methods and systems described herein.

The OAMB-polyamide particles may be useful in applications that include,but are not limited to, paints, powder coatings, ink jet materials,electrophotographic toners, 3-D printing, and the like.

By way of nonlimiting example, 3-D printing processes of the presentdisclosure may comprise: depositing OAMB-polyamide particles in thepresent disclosure (and optionally one or more other thermoplasticpolymers and/or one or more compatibilizers) optionally in combinationwith other particles comprising one or more thermoplastic polymersand/or one or more compatibilizers upon a surface in a specified shape,and once deposited, heating at least a portion of the particles topromote consolidation thereof and form a consolidated body (or object orarticle), such that the consolidated body has a void percentage of about1% or less after being consolidated. For example, heating andconsolidation of the thermoplastic polymer particles may take place in a3-D printing apparatus employing a laser, such that heating andconsolidation take place by selective laser sintering.

Examples of articles that may be produced by such methods where theOAMB-polyamide may be all or a portion of said articles include, but arenot limited to, particles, films, packaging, toys, household goods,automotive parts, aerospace/aircraft-related parts, containers (e.g.,for food, beverages, cosmetics, personal care compositions, medicine,and the like), shoe soles, furniture parts, decorative home goods,plastic gears, screws, nuts, bolts, cable ties, jewelry, art, sculpture,medical items, prosthetics, orthopedic implants, production of artifactsthat aid learning in education, 3-D anatomy models to aid in surgeries,robotics, biomedical devices (orthotics), home appliances, dentistry,electronics, sporting goods, and the like.

The OAMB-polyamides described herein may have a specific chemicalfingerprint that is useful in identifying objects, tracking objects,authenticating objects, and/or determining the health of objects.Further, the placement of where the OAMB-polyamides are located in theobjects is another layer of fingerprinting the objects for identifyingobjects, tracking objects, authenticating objects, and/or determiningthe health of objects.

Methods of identifying objects, tracking objects, authenticatingobjects, and/or determining the health of objects may include (a)exposing the object comprising OAMB-polyamides to electromagneticradiation (e.g., for fluorophores preferably at a wavelength of 302 nmor less or 700 nm or greater); (b) sensing one or more spectra relatedto the electromagnetic radiation absorbed and/or reemitted (e.g., forfluorophores preferably the photoluminescence emitted between 302 nm to700 nm); and (c) comparing the spectra to the known spectra for theoptical absorbers used in said object or portion thereof. Optionally,the location of where the spectra area is located on the object may becompared to the known location where the spectra area should be. Thecomparison(s) can be used for identifying and/or authenticating theobject. For tracking, the comparison(s) may be done and/or the detectedspectra and/or spectra area may be logged into a database along with thephysical location of the object. Further, the health of objects thatwear and/or crack can be ascertained. For example, a core portion of thearticle may comprise optical absorbers and an outer portion may coverthe core portion and not comprise the optical absorbers (or comprisedifferent optical absorbers). Then, when comparing spectra, theappearance of spectral features for the optical absorbers in the coremay indicate that the object is at or near the end of life.

EXAMPLE EMBODIMENTS

A first nonlimiting example embodiment is a method comprising:esterifying a hydroxyl-pendent optical absorber with a halogen-terminalaliphatic acid to yield a halogen-terminal alkyl-optical absorber; andN-alkylating a polyamide with the halogen-terminal alkyl-opticalabsorber to yield a polyamide having an optical absorber pendent fromthe polyamide's backbone (OAMB-polyamide). The first nonlimiting exampleembodiment may include one or more of: Element 1: wherein thehalogen-terminal aliphatic acid is a chloro aliphatic acid or a bromoaliphatic acid; Element 2: wherein the halogen-terminal aliphatic acidis a C₂ to C₁₈ halogen-terminal aliphatic acid; Element 3: wherein thehydroxyl-pendent optical absorber is selected from the group consistingof: 1,2-dihydroxyanthraquinone; carminic acid;1,3-dihydroxyanthraquinone; 1,4-dihydroxyanthraquinone;1-hydroxy-4-(p-tolylamino)anthraquinone;1,8-dihydroxy-3-methoxy-6-methylanthraquinone;1,2,5-trihydroxy-6-methylanthracene-9,10-dione; calcein;6-carboxyfluorescein succinimidyl ester; 6-carboxyfluorescein;2′,7′-dichloro-3′,6′-dihydroxy-3H-spiro[2-benzofuran-1,9′-xanthen]-3-one;fluorescein isothiocyanate; 4′,5′-dibromofluorescein;5(6)-carboxy-2′,7′-dichlorofluorescein;4-chloro-3-[(2Z)-2-[1-[5-chloro-4-[[(2Z)-2-[[2-chloro-5-[N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]-C-hydroxycarbonimidoyl]phenyl]hydrazinylidene]-3-oxobutanoyl]amino]-2-methylanilino]-1,3-dioxobutan-2-ylidene]hydrazinyl]-N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]benzenecarboximidicacid;2-[(3-carboxy-2-oxidonaphthalen-1-yl)diazenyl]-4-chloro-5-methylbenzenesulfonatedisodium; phenol dyes; 3,3-bis(4-hydroxyphenyl)-2-benzofuran-1-one;4,8-diamino-1,5-dihydroxy-9,10-dioxoanthracene-2-sulfonate sodium;1-amino-4-hydroxy-2-phenoxyanthracene-9,10-dione;5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylatetrisodium;5-chloro-2-hydroxy-3-[(3-methyl-5-oxo-1-phenyl-4H-pyrazol-4-yl)diazenyl]benzenesulfonatesodium;2-[(4-hydroxy-9,10-dioxoanthracen-1-yl)amino]-5-methylbenzenesulfonicacid;3,5,6,8-tetrahydroxy-1-methyl-9,10-dioxo-7-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]anthracene-2-carboxylicacid; and the like; and any combination thereof; Element 4: wherein thepolyamide is selected from the group consisting of: polycaproamide,poly(hexamethylene succinamide), polyhexamethylene adipamide,polypentamethylene adipamide, polyhexamethylene sebacamide,polyundecamide, polydodecamide, polyhexamethylene terephthalamide, nylon10,10, nylon 10,12, nylon 10,14, nylon 10,18, nylon 6,18, nylon 6,12,nylon 6,14, nylon 12,12, a semi-aromatic polyamide, an aromaticpolyamide, any copolymer thereof, and any combination thereof; Element5: wherein the halogen-terminal aliphatic acid is X—(CH₂)_(n)—COOH whereX is bromo or chloro and n is 1-17; Element 6: wherein thehalogen-terminal aliphatic acid is selected from the group consistingof: bromoacetic acid, chloroacetic acid, 3-bromopropionic acid,3-chloropropionic acid, 4-bromobutyric acid, 4-chlorobutyric acid,5-bromovaleric acid, 5-chlorovaleric acid, 6-bromohexanoic acid,6-chlorohexanoic acid, and any combination thereof; Element 7: whereinesterifying is at about 0° C. to about 70° C.; Element 8: whereinesterifying is for about 10 minutes to about 24 hours; Element 9:wherein a molar ratio of the hydroxyl-pendent optical absorber to thehalogen-terminal aliphatic acid is about 5:1 to about 1:5; element 10:wherein the N-alkylating is at about 100° C. to about 200° C.; Element11: wherein the N-alkylating is for about 10 minutes to about 48 hours;Element 12: wherein a molar ratio of the halogen-terminal alkyl-opticalabsorber to the polyamide is preferably about 500:1 to about 10:1.Examples of combinations include, but are not limited to, Element 1 incombination with one or more of Elements 2-12; Element 2 in combinationwith one or more of Elements 3-12; Element 3 in combination with one ormore of Elements 4-12; Element 4 in combination with one or more ofElements 5-12; Element 5 in combination with one or more of Elements6-12; Element 6 in combination with one or more of Elements 7-12;Element 7 in combination with one or more of Elements 8-12; Element 8 incombination with one or more of Elements 9-12; Element 9 in combinationwith one or more of Elements 10-12; Element 10 in combination with oneor more of Elements 11-12; and Elements 11 and 12 in combination.

A second nonlimiting example embodiment is a method comprising:esterifying a carboxyl-pendent optical absorber with a halogen-terminalaliphatic alcohol to yield a halogen-terminal alkyl-optical absorber;and N-alkylating a polyamide with the modified optical absorber to yielda polyamide having an optical absorber pendent from the polyamide'sbackbone (OAMB-polyamide). The second nonlimiting example embodiment mayinclude one or more of: Element 13: wherein the carboxyl-pendent opticalabsorber is selected from the group consisting of: calcein;5(6)-carboxyfluorescein; 6-carboxyfluorescein;5(6)-carboxyfluorescein-N-hydroxysuccinimide ester; 2-pyrenepropanoicacid; 2-perylenepropanoic acid; 3,9-perylenedicarboxylic acid;5(6)-carboxy-2′,7′-dichlorofluorescein; calcein blue;2-[(3-carboxy-2-oxidonaphthalen-1-yl)diazenyl]-4-chloro-5-methylbenzenesulfonatedisodium;5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylatetrisodium; and the like; and any combination thereof; Element 14:wherein the polyamide is selected from the group consisting of:polycaproamide, poly(hexamethylene succinamide), polyhexamethyleneadipamide, polypentamethylene adipamide, polyhexamethylene sebacamide,polyundecamide, polydodecamide, polyhexamethylene terephthalamide, nylon10,10, nylon 10,12, nylon 10,14, nylon 10,18, nylon 6,18, nylon 6,12,nylon 6,14, nylon 12,12, a semi-aromatic polyamide, an aromaticpolyamide, any copolymer thereof, and any combination thereof; Element15: wherein the halogen-terminal aliphatic alcohol is X—(CH₂)_(n)—OHwhere X is bromo or chloro and n is 2-18; Element 16: wherein thehalogen-terminal aliphatic alcohol is selected from the group consistingof: 3-bromoethan-1-ol, 3-chloroethan-1-ol, 4-bromopropan-1-ol,4-chloropropan-1-ol, 5-bromopbutan-1-ol, 5-chlorobutan-1-ol,6-bromopentan-1-ol, 6-chloropentan-1-ol, 7-bromohexan-1-ol,7-chlorohexan-1-ol, and any combination thereof; Element 17: whereinesterifying is at about 0° C. to about 70° C.; Element 18: whereinesterifying is for about 10 minutes to about 24 hours; Element 19:wherein a molar ratio of the carboxyl-pendent optical absorber to thehalogen-terminal aliphatic alcohol is about 5:1 to about 1:5; Element20: wherein the N-alkylating is at about 100° C. to about 200° C.;Element 21: wherein the N-alkylating is for about 10 minutes to about 48hours; and Element 22: wherein a molar ratio of the halogen-terminalalkyl-optical absorber to the polyamide is preferably about 500:1 toabout 10:1. Examples of combinations include, but are not limited to,Element 13 in combination with one or more of Elements 14-22; Element 14in combination with one or more of Elements 15-22; Element 15 incombination with one or more of Elements 16-22; Element 16 incombination with one or more of Elements 17-22; Element 17 incombination with one or more of Elements 18-22; Element 18 incombination with one or more of Elements 19-22; Element 19 incombination with one or more of Elements 20-22; Element 20 incombination with one or more of Elements 21-22; and Elements 21 and 22in combination.

A third nonlimiting example embodiment is a composition comprising: apolyamide having an optical absorber pendent from a backbone of thepolyamide, wherein the polyamide and the optical absorber are connectedby an alkyl linker. The third nonlimiting example embodiment may includeone or more of: Element 23: wherein the optical absorber is selectedfrom the group consisting of: 1,2-dihydroxyanthraquinone; carminic acid;1,3-dihydroxyanthraquinone; 1,4-dihydroxyanthraquinone;1-hydroxy-4-(p-tolylamino)anthraquinone;1,8-dihydroxy-3-methoxy-6-methylanthraquinone;1,2,5-trihydroxy-6-methylanthracene-9,10-dione; calcein;6-carboxyfluorescein succinimidyl ester; 6-carboxyfluorescein;2′,7′-dichloro-3′,6′-dihydroxy-3H-spiro[2-benzofuran-1,9′-xanthen]-3-one;fluorescein isothiocyanate; 4′,5′-dibromofluorescein;5(6)-carboxy-2′,7′-dichlorofluorescein;4-chloro-3-[(2Z)-2-[1-[5-chloro-4-[[(2Z)-2-[[2-chloro-5-[N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]-C-hydroxycarbonimidoyl]phenyl]hydrazinylidene]-3-oxobutanoyl]amino]-2-methylanilino]-1,3-dioxobutan-2-ylidene]hydrazinyl]-N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]benzenecarboximidicacid;2-[(3-carboxy-2-oxidonaphthalen-1-yl)diazenyl]-4-chloro-5-methylbenzenesulfonatedisodium; phenol dyes; 3,3-bis(4-hydroxyphenyl)-2-benzofuran-1-one;4,8-diamino-1,5-dihydroxy-9,10-dioxoanthracene-2-sulfonate sodium;1-amino-4-hydroxy-2-phenoxyanthracene-9,10-dione;5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylatetrisodium;5-chloro-2-hydroxy-3-[(3-methyl-5-oxo-1-phenyl-4H-pyrazol-4-yl)diazenyl]benzenesulfonatesodium;2-[(4-hydroxy-9,10-dioxoanthracen-1-yl)amino]-5-methylbenzenesulfonicacid;3,5,6,8-tetrahydroxy-1-methyl-9,10-dioxo-7-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]anthracene-2-carboxylicacid; and the like; and any combination thereof; Element 24: wherein thealkyl linker has 2-18 carbons; Element 25: wherein the alkyl linker ishas 2-6 carbons; and Element 26: wherein the polyamide is selected fromthe group consisting of: polycaproamide, poly(hexamethylenesuccinamide), polyhexamethylene adipamide, polypentamethylene adipamide,polyhexamethylene sebacamide, polyundecamide, polydodecamide,polyhexamethylene terephthalamide, nylon 10,10, nylon 10,12, nylon10,14, nylon 10,18, nylon 6,18, nylon 6,12, nylon 6,14, nylon 12,12, asemi-aromatic polyamide, an aromatic polyamide, any copolymer thereof,and any combination thereof.

A fourth nonlimiting example embodiment is a method comprising:extruding a polymer melt comprising the third nonlimiting exampleembodiment (optionally including one or more of Elements 24-26) throughan orifice to produce a film, a fiber (or a filament), particles,pellets, or the like

A fifth article comprising: the polyamide of the third nonlimitingexample embodiment (optionally including one or more of Elements 24-26).

A sixth nonlimiting example embodiment is a method comprising: mixing amixture comprising a polyamide having an optical absorber pendent from abackbone of the polyamide (OAMB-polyamide), a carrier fluid that isimmiscible with the OAMB-polyamide, and optionally an emulsionstabilizer at a temperature greater than a melting point or softeningtemperature of the OAMB-polyamide and at a shear rate sufficiently highto disperse the OAMB-polyamide in the carrier fluid; and cooling themixture to below the melting point or softening temperature of theOAMB-polyamide to form solidified particles comprising theOAMB-polyamide and the emulsion stabilizer, when present, associatedwith an outer surface of the solidified particles. The sixth nonlimitingexample embodiment may further include one or more of: Element 27:wherein the emulsion stabilizer is included in the mixture, and whereinthe emulsion stabilizer associated with an outer surface of thesolidified particles; Element 28: wherein the mixture further comprisesa thermoplastic polymer that is not the OAMB-polyamide; Element 29:wherein the mixture further comprises a polyamide but without an opticalabsorber pendent therefrom; Element 30: wherein the optical absorber isfrom a family selected from the group consisting of: rhodamines,fluoresceins, coumarins, naphthalimides, benzoxanthenes, acridines,cyanines, oxazins, phenanthridine, pyrrole ketones, benzaldehydes,polymethines, triarylmethanes, anthraquinones, pyrazolones,quinophthalones, carbonyl dyes, diazo dyes, perinones,diketopyrrolopyrrole (DPP), dioxazine dyes, phthalocyanines,indanthrenes, benzanthrone, violanthrones, azo dyes, phthalocyaninedyes, quinacridone dyes, anthraquinone dyes, dioxagine dyes, indigodyes, thioindigo dyes, perinone dyes, perylene dyes, isoindolene dyes,aromatic amino acids, flavins, derivatives of pyridoxyl, derivatives ofchlorophyll, and any combination thereof; Element 31: wherein thepolyamide is selected from the group consisting of: polycaproamide,poly(hexamethylene succinamide), polyhexamethylene adipamide,polypentamethylene adipamide, polyhexamethylene sebacamide,polyundecamide, polydodecamide, polyhexamethylene terephthalamide, nylon10,10, nylon 10,12, nylon 10,14, nylon 10,18, nylon 6,18, nylon 6,12,nylon 6,14, nylon 12,12, a semi-aromatic polyamide, an aromaticpolyamide, any copolymer thereof, and any combination thereof; Element32: wherein the OAMB-polyamide comprises an alkyl linker connecting thepolyamide and the optical absorber; Element 33: Element 32 and whereinthe alkyl linker has 2-18 carbons; Element 34: Element 32 and whereinthe alkyl linker has 2-6 carbons; Element 35: wherein at least some ofthe solidified particles have a void comprising the emulsion stabilizerat a void/polymer interface; Element 36: Element 35 and wherein theemulsion stabilizer comprises nanoparticles and the nanoparticles areembedded in the void/polymer interface; Element 37: Element 35 andwherein the void contains the carrier fluid; Element 38: wherein thesolidified particles further comprises elongated structures on thesurface of the solidified particles, wherein the elongated structurescomprises the OAMB-polyamide with the emulsion stabilizer associatedwith an outer surface of the elongated structures; Element 39: whereinthe emulsion stabilizer forms a coating that covers less than 5% of thesurface of the solidified particles; Element 40: wherein the emulsionstabilizer forms a coating that covers at least 5% of the surface of thesolidified particles; Element 41: wherein the emulsion stabilizer formsa coating that covers at least 25% of the surface of the solidifiedparticles; Element 42: wherein the emulsion stabilizer forms a coatingthat covers at least 50% of the surface of the solidified particles;Element 43: wherein the OAMB-polyamide is present in the mixture at 5 wt% to 60 wt % of the mixture; Element 44: wherein the emulsion stabilizeris present in the mixture at 0.05 wt % to 5 wt % by weight of theOAMB-polyamide; Element 45: wherein the nanoparticles have an averagediameter of 1 nm to 500 nm; Element 46: wherein the carrier fluid isselected from the group consisting of: silicone oil, fluorinatedsilicone oils, perfluorinated silicone oils, polyethylene glycols,paraffins, liquid petroleum jelly, vison oils, turtle oils, soya beanoils, perhydrosqualene, sweet almond oils, calophyllum oils, palm oils,parleam oils, grapeseed oils, sesame oils, maize oils, rapeseed oils,sunflower oils, cottonseed oils, apricot oils, castor oils, avocadooils, jojoba oils, olive oils, cereal germ oils, esters of lanolic acid,esters of oleic acid, esters of lauric acid, esters of stearic acid,fatty esters, higher fatty acids, fatty alcohols, polysiloxanes modifiedwith fatty acids, polysiloxanes modified with fatty alcohols,polysiloxanes modified with polyoxy alkylenes, and any combinationthereof; Element 47: wherein the silicone oil is selected from the groupconsisting of: polydimethylsiloxane, methylphenylpolysiloxane, an alkylmodified polydimethylsiloxane, an alkyl modifiedmethylphenylpolysiloxane, an amino modified polydimethylsiloxane, anamino modified methylphenylpolysiloxane, a fluorine modifiedpolydimethylsiloxane, a fluorine modified methylphenylpolysiloxane, apolyether modified polydimethylsiloxane, a polyether modifiedmethylphenylpolysiloxane, and any combination thereof; Element 48:wherein the carrier fluid has a viscosity at 25° C. of 1,000 cSt to150,000 cSt; Element 49: wherein the carrier fluid has a density of 0.6g/cm3 to 1.5 g/cm3; Element 50: wherein mixing occurs in an extruder;Element 51: wherein mixing occurs in a stirred reactor; Element 52:wherein the mixture further comprises a surfactant; Element 53: whereinthe particles have a D10 of about 0.1 μm to about 125 μm, a D50 of about0.5 μm to about 200 μm, and a D90 of about 3 μm to about 300 μm, whereinD10<D50<D90; Element 54: wherein the particles have a diameter span ofabout 0.2 to about 10; Element 55: wherein the particles have a D10 ofabout 5 μm to about 30 μm, a D50 of about 30 μm to about 70 μm, and aD90 of about 70 μm to about 120 μm, wherein D10<D50<D90; Element 56:wherein the particles have a diameter span of about 1.0 to about 2.5;Element 57: wherein the particles have a D10 of about 25 μm to about 60μm, a D50 of about 60 μm to about 110 μm, and a D90 of about 110 μm toabout 175 μm, wherein D10<D50<D90; Element 58: wherein the particleshave a diameter span of about 0.6 to about 1.5; Element 59: wherein theparticles have a D10 of about 75 μm to about 125 μm, a D50 of about 100μm to about 200 μm, and a D90 of about 125 μm to about 300 μm, whereinD10<D50<D90; Element 60: wherein the particles have a diameter span ofabout 0.2 to about 1.2; Element 61: wherein the solidified particleshave a circularity of about 0.90 to about 1.0; Element 62: wherein thesolidified particles have a Hausner ratio of about 1.0 to about 1.5.Element 63: wherein the nanoparticles comprise oxide nanoparticles;Element 38: wherein the nanoparticles comprise carbon black; and Element64: wherein the nanoparticles comprise polymer nanoparticles. Examplesof combinations include, but are not limited to, two or more of Elements27-34 in combination and optionally in further combination with one ormore of Elements 35-65; two or more of Elements 33-36 in combination;two or more of Elements 44-47 in combination; Elements 51 and 52 incombination; Elements 53 and 54 in combination; Elements 55 and 56 incombination; Elements 57 and 58 in combination; one or more of Elements51-58 in combination with Element 60 and/or Element 35; two or more ofElements 53-65 in combination; and two or more of Elements 45, 52, 63,64, and 65 in combination.

A seventh nonlimiting example embodiment is a composition comprising:particles (solidified particles) comprising a polyamide having anoptical absorber pendent from a backbone of the polyamide(OAMB-polyamide) and having a circularity of about 0.90 to about 1.0.The seventh nonlimiting example embodiment may further include one ormore of: Element 53; Element 54; Element 55; Element 56; Element 57;Element 58; Element 59; Element 60; Element 61; Element 62; Element 66:wherein the particles further comprise a thermoplastic polymer that isnot the OAMB-polyamide; Element 67: wherein the particles furthercomprise the polyamide but without an optical absorber pendenttherefrom; Element 68: wherein the particles further comprise anemulsion stabilizer associated with an outer surface of the particles;Element 69: wherein at least some of the particles have a voidcomprising the emulsion stabilizer at a void/polymer interface; Element70: Element 69 and wherein the emulsion stabilizer comprisesnanoparticles and the nanoparticles are embedded in the void/polymerinterface; Element 71: Element 69 and wherein the void contains thecarrier fluid; Element 72: wherein the particles further compriseselongated structures on the surface of the solidified particles, whereinthe elongated structures comprises the OAMB-polyamide with the emulsionstabilizer associated with an outer surface of the elongated structures;Element 73: wherein the emulsion stabilizer forms a coating that coversless than 5% of the surface of the solidified particles; Element 74:wherein the emulsion stabilizer forms a coating that covers at least 5%of the surface of the solidified particles; Element 75: wherein theemulsion stabilizer forms a coating that covers at least 25% of thesurface of the solidified particles; Element 76: wherein the emulsionstabilizer forms a coating that covers at least 50% of the surface ofthe solidified particles; and Element 77: wherein emulsion stabilizercomprises nanoparticles having an average diameter of 1 nm to 500 nm.Examples of combinations include, but are not limited to, two or more ofElements 53-62 in combination; one or more of Elements 53-62 incombination with one or more of Elements 67-77; and two or more ofElements 67-77 in combination.

A eighth nonlimiting example embodiment is a method comprising:depositing OAMB-polyamide particles of the second nonlimiting example(optionally including one or more of Elements 53-62 and 67-77) upon asurface in a specified shape; and once deposited, heating at least aportion of the particles to promote consolidation thereof and form aconsolidated body.

Clauses

-   -   Clause 1. A method comprising: esterifying a hydroxyl-pendent        optical absorber with a halogen-terminal aliphatic acid to yield        a halogen-terminal alkyl-optical absorber; and N-alkylating a        polyamide with the halogen-terminal alkyl-optical absorber to        yield a polyamide having an optical absorber pendent from the        polyamide's backbone (OAMB-polyamide).    -   Clause 2. The method of Clause 1, wherein the halogen-terminal        aliphatic acid is a chloro aliphatic acid or a bromo aliphatic        acid.    -   Clause 3. The method of Clause 1, wherein the halogen-terminal        aliphatic acid is a C₂ to C₁₈ halogen-terminal aliphatic acid.    -   Clause 4. The method of Clause 1, wherein the hydroxyl-pendent        optical absorber is selected from the group consisting of:        1,2-dihydroxyanthraquinone; carminic acid;        1,3-dihydroxyanthraquinone; 1,4-dihydroxyanthraquinone;        1-hydroxy-4-(p-tolylamino)anthraquinone;        1,8-dihydroxy-3-methoxy-6-methyl anthraquinone;        1,2,5-trihydroxy-6-methylanthracene-9,10-dione; calcein;        6-carboxyfluorescein succinimidyl ester; 6-carboxyfluorescein;        2′,7′-dichloro-3′,6′-dihydroxy-3H-spiro[2-benzofuran-1,9′-xanthen]-3-one;        fluorescein isothiocyanate; 4′,5′-dibromofluorescein;        5(6)-carboxy-2′,7′-dichlorofluorescein;        4-chloro-3-[(2Z)-2-[1-[5-chloro-4-[(2Z)-2-[[2-chloro-5-[N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]-C-hydroxycarbonimidoyl]phenyl]hydrazinylidene]-3-oxobutanoyl]amino]-2-methylanilino]-1,3-dioxobutan-2-ylidene]hydrazinyl]-N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]benzenecarboximidic        acid;        2-[(3-carboxy-2-oxidonaphthalen-1-yl)diazenyl]-4-chloro-5-methylbenzenesulfonate        disodium; phenol dyes; 3,3-bi s (4-hydroxy        phenyl)-2-benzofuran-1-one; 4,8-diamino-1,5-dihydroxy-9,10-di        oxoanthracene-2-sulfonate sodium;        1-amino-4-hydroxy-2-phenoxyanthracene-9,10-dione;        5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylate        trisodium;        5-chloro-2-hydroxy-3-[(3-methyl-5-oxo-1-phenyl-4H-pyrazol-4-yl)diazenyl]benzenesulfonate        sodium;        2-[(4-hydroxy-9,10-dioxoanthracen-1-yl)amino]-5-methylbenzenesulfonic        acid; 3,5,6,8-tetrahydroxy-1-methyl-9,10-di        oxo-7-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]anthracene-2-carboxylic        acid; and the like; and any combination thereof.    -   Clause 5. The method of Clause 1, wherein the polyamide is        selected from the group consisting of: polycaproamide,        poly(hexamethylene succinamide), polyhexamethylene adipamide,        polypentamethylene adipamide, polyhexamethylene sebacamide,        polyundecamide, polydodecamide, polyhexamethylene        terephthalamide, nylon 10,10, nylon 10,12, nylon 10,14, nylon        10,18, nylon 6,18, nylon 6,12, nylon 6,14, nylon 12,12, a        semi-aromatic polyamide, an aromatic polyamide, any copolymer        thereof, and any combination thereof.    -   Clause 6. The method of Clause 1, wherein the halogen-terminal        aliphatic acid is X—(CH₂)_(n)—COOH where X is bromo or chloro        and n is 1-17.    -   Clause 7. The method of Clause 1, wherein the halogen-terminal        aliphatic acid is selected from the group consisting of:        bromoacetic acid, chloroacetic acid, 3-bromopropionic acid,        3-chloropropionic acid, 4-bromobutyric acid, 4-chlorobutyric        acid, 5-bromovaleric acid, 5-chlorovaleric acid, 6-bromohexanoic        acid, 6-chlorohexanoic acid, and any combination thereof.    -   Clause 8. The method of Clause 1, wherein esterifying is at        about 0° C. to about 70° C.    -   Clause 9. The method of Clause 1, wherein esterifying is for        about 10 minutes to about 24 hours.    -   Clause 10. The method of Clause 1, wherein a molar ratio of the        hydroxyl-pendent optical absorber to the halogen-terminal        aliphatic acid is about 5:1 to about 1:5.    -   Clause 11. The method of Clause 1, wherein the N-alkylating is        at about 100° C. to about 200° C.    -   Clause 12. The method of Clause 1, wherein the N-alkylating is        for about 10 minutes to about 48 hours.    -   Clause 13. The method of Clause 1, wherein a molar ratio of the        halogen-terminal alkyl-optical absorber to the polyamide is        preferably about 500:1 to about 10:1.    -   Clause 14. A method comprising: esterifying a carboxyl-pendent        optical absorber with a halogen-terminal aliphatic alcohol to        yield a halogen-terminal alkyl-optical absorber; and        N-alkylating a polyamide with the modified optical absorber to        yield a polyamide having an optical absorber pendent from the        polyamide's backbone (OAMB-polyamide).    -   Clause 15. The method of Clause 14, wherein the carboxyl-pendent        optical absorber is selected from the group consisting of:        calcein; 5(6)-carboxyfluorescein; 6-carboxyfluorescein;        5(6)-carboxyfluorescein-N-hydroxysuccinimide ester;        2-pyrenepropanoic acid; 2-perylenepropanoic acid;        3,9-perylenedicarboxylic acid; 5(6)-carboxy-2′,7′-di        chlorofluores cein; calcein blue;        2-[(3-carboxy-2-oxidonaphthalen-1-yOdiazenyl]-4-chloro-5-methylbenzenesulfonate        disodium;        5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylate        trisodium; and the like; and any combination thereof.    -   Clause 16. The method of Clause 14, wherein the polyamide is        selected from the group consisting of: polycaproamide,        poly(hexamethylene succinamide), polyhexamethylene adipamide,        polypentamethylene adipamide, polyhexamethylene sebacamide,        polyundecamide, polydodecamide, polyhexamethylene        terephthalamide, nylon 10,10, nylon 10,12, nylon 10,14, nylon        10,18, nylon 6,18, nylon 6,12, nylon 6,14, nylon 12,12, a        semi-aromatic polyamide, an aromatic polyamide, any copolymer        thereof, and any combination thereof.    -   Clause 17. The method of Clause 14, wherein the halogen-terminal        aliphatic alcohol is X—(CH₂)_(n)—OH where X is bromo or chloro        and n is 2-18.    -   Clause 18. The method of Clause 14, wherein the halogen-terminal        aliphatic alcohol is selected from the group consisting of:        3-bromoethan-1-ol, 3-chloroethan-1-ol, 4-bromopropan-1-ol,        4-chloropropan-1-ol, 5-bromopbutan-1-ol, 5-chlorobutan-1-ol,        6-bromopentan-1-ol, 6-chloropentan-1-ol, 7-bromohexan-1-ol,        7-chlorohexan-1-ol, and any combination thereof.    -   Clause 19. The method of Clause 14, wherein esterifying is at        about 0° C. to about 70° C.    -   Clause 20. The method of Clause 14, wherein esterifying is for        about 10 minutes to about 24 hours.    -   Clause 21. The method of Clause 14, wherein a molar ratio of the        carboxyl-pendent optical absorber to the halogen-terminal        aliphatic alcohol is about 5:1 to about 1:5.    -   Clause 22. The method of Clause 14, wherein the N-alkylating is        at about 100° C. to about 200° C.    -   Clause 23. The method of Clause 14, wherein the N-alkylating is        for about 10 minutes to about 48 hours.    -   Clause 24. The method of Clause 14, wherein a molar ratio of the        halogen-terminal alkyl-optical absorber to the polyamide is        preferably about 500:1 to about 10:1.    -   Clause 25. A composition comprising: a polyamide having an        optical absorber pendent from a backbone of the polyamide,        wherein the polyamide and the optical absorber are connected by        an alkyl linker.    -   Clause 26. The composition of Clause 25, wherein the alkyl        linker has 2-18 carbons.    -   Clause 27. The composition of Clause 25, wherein the alkyl        linker is has 2-6 carbons.    -   Clause 28. The composition of Clause 25, wherein the optical        absorber is selected from the group consisting of:        1,2-dihydroxyanthraquinone; carminic acid;        1,3-dihydroxyanthraquinone; 1,4-dihydroxyanthraquinone;        1-hydroxy-4-(p-tolylamino)anthraquinone;        1,8-dihydroxy-3-methoxy-6-methyl anthraquinone;        1,2,5-trihydroxy-6-methylanthracene-9,10-dione; calcein;        6-carboxyfluorescein succinimidyl ester; 6-carboxyfluorescein;        2′,7′-dichloro-3′,6′-dihydroxy-3H-spiro[2-benzofuran-1,9′-xanthen]-3-one;        fluorescein isothiocyanate; 4′,5′-dibromofluorescein;        5(6)-carboxy-2′,7′-dichlorofluorecein;        4-chloro-3-[(2Z)-2-[1-[5-chloro-4-[[(2Z)-2-[[2-chloro-5-[N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]-C-hydroxy        carbonimidoyl]phenyl]hydrazinylidene]-3-oxobutanoyl]amino]-2-methylanilino]-1,3-dioxobutan-2-ylidene]hydrazinyl]-N-[2-(4-chlorophenoxy)-5-(trifluoromethyl)phenyl]benzenecarboximidic        acid;        2-[(3-carboxy-2-oxidonaphthalen-1-yl)diazenyl]-4-chloro-5-methylbenzenesulfonate        disodium; phenol dyes;        3,3-bis(4-hydroxyphenyl)-2-benzofuran-1-one;        4,8-diamino-1,5-dihydroxy-9,10-di oxoanthracene-2-sulfonate        sodium; 1-amino-4-hydroxy-2-phenoxyanthracene-9,10-dione;        5-oxo-1-(4-sulfonatophenyl)-4-[(4-sulfonatophenyl)diazenyl]-4H-pyrazole-3-carboxylate        trisodium;        5-chloro-2-hydroxy-3-[(3-methyl-5-oxo-1-phenyl-4H-pyrazol-4-yl)diazenyl]benzenesulfonate        sodium; 2-[(4-hydroxy-9,10-di oxo        anthracen-1-yl)amino]-5-methylbenzenesulfonic acid;        3,5,6,8-tetrahydroxy-1-methyl-9,10-di        oxo-7-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]anthracene-2-carboxylic        acid; and the like; and any combination thereof.    -   Clause 29. The composition of Clause 25, wherein the polyamide        is selected from the group consisting of: polycaproamide,        poly(hexamethylene succinamide), polyhexamethylene adipamide,        polypentamethylene adipamide, polyhexamethylene sebacamide,        polyundecamide, polydodecamide, polyhexamethylene        terephthalamide, nylon 10,10, nylon 10,12, nylon 10,14, nylon        10,18, nylon 6,18, nylon 6,12, nylon 6,14, nylon 12,12, a        semi-aromatic polyamide, an aromatic polyamide, any copolymer        thereof, and any combination thereof.    -   Clause 30. A method comprising: depositing particles upon a        surface in a specified shape, wherein the particles comprise the        polyamide of Clause 25; and once deposited, heating at least a        portion of the particles to promote consolidation thereof and        form a consolidated body.    -   Clause 31. The method of Clause 30, wherein the particles        further comprise a thermoplastic polymer selected from the group        consisting of: polyamide, polyurethane, polyethylene,        polypropylene, polyacetal, polycarbonate, polybutylene        terephthalate, polyethylene terephthalate, polyethylene        naphthalate, polytrimethylene terephthalate, polyhexamethylene        terephthalate, polystyrene, polyvinyl chloride,        polytetrafluoroethene, polyester, polyether, polyether sulfone,        polyetherether ketone, polyacrylate, polymethacrylate,        polyimide, acrylonitrile butadiene styrene, polyphenylene        sulfide, vinyl polymer, polyarylene ether, polyarylene sulfide,        polysulfone, polyether ketone, polyamide-imide, polyetherimide,        polyetherester, copolymers comprising a polyether block and a        polyamide block, grafted or ungrafted thermoplastic polyolefin,        functionalized or nonfunctionalized ethylene/vinyl monomer        polymer, functionalized or nonfunctionalized ethylene/alkyl        (meth)acrylate, functionalized or nonfunctionalized        (meth)acrylic acid polymer, functionalized or nonfunctionalized        ethylene/vinyl monomer/alkyl (meth)acrylate terpolymer,        ethylene/vinyl monomer/carbonyl terpolymer, ethylene/alkyl        (meth)acrylate/carbonyl terpolymer,        methylmethacrylate-butadiene-styrene type core-shell polymer,        polystyrene-block-polybutadiene-block-poly(methyl methacrylate)        block terpolymer, chlorinated or chlorosulphonated polyethylene,        polyvinylidene fluoride, phenolic resin, poly(ethylene/vinyl        acetate), polybutadiene, polyisoprene, styrenic block copolymer,        polyacrylonitrile, silicone, and any combination thereof.    -   Clause 32. An article comprising: the polyamide of Clause 25.    -   Clause 33. A method comprising: mixing a mixture comprising a        polyamide having an optical absorber pendent from a backbone of        the polyamide (OAMB-polyamide), a carrier fluid that is        immiscible with the OAMB-polyamide, and optionally an emulsion        stabilizer at a temperature greater than a melting point or        softening temperature of the OAMB-polyamide and at a shear rate        sufficiently high to disperse the OAMB-polyamide in the carrier        fluid; and cooling the mixture to below the melting point or        softening temperature of the OAMB-polyamide to form solidified        particles comprising the OAMB-polyamide and the emulsion        stabilizer, when present, associated with an outer surface of        the solidified particles.    -   Clause 34. The method of Clause 33, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer associated with an outer surface of the solidified        particles.    -   Clause 35. The method of Clause 33, wherein the mixture further        comprises a thermoplastic polymer that is not the        OAMB-polyamide.    -   Clause 36. The method of Clause 33, wherein the mixture further        comprises the polyamide but without an optical absorber pendent        therefrom.    -   Clause 37. The method of Clause 33, wherein the optical absorber        is from a family selected from the group consisting of:        rhodamines, fluoresceins, coumarins, naphthalimides,        benzoxanthenes, acridines, cyanines, oxazins, phenanthridine,        pyrrole ketones, benzaldehydes, polymethines, triarylmethanes,        anthraquinones, pyrazolones, quinophthalones, carbonyl dyes,        diazo dyes, perinones, diketopyrrolopyrrole (DPP), dioxazine        dyes, phthalocyanines, indanthrenes, benzanthrone,        violanthrones, azo dyes, phthalocyanine dyes, quinacridone dyes,        anthraquinone dyes, dioxagine dyes, indigo dyes, thioindigo        dyes, perinone dyes, perylene dyes, isoindolene dyes, aromatic        amino acids, flavins, derivatives of pyridoxyl, derivatives of        chlorophyll, and any combination thereof.    -   Clause 38. The method of Clause 33, wherein the polyamide is        selected from the group consisting of: polycaproamide,        poly(hexamethylene succinamide), polyhexamethylene adipamide,        polypentamethylene adipamide, polyhexamethylene sebacamide,        polyundecamide, polydodecamide, polyhexamethylene        terephthalamide, nylon 10,10, nylon 10,12, nylon 10,14, nylon        10,18, nylon 6,18, nylon 6,12, nylon 6,14, nylon 12,12, a        semi-aromatic polyamide, an aromatic polyamide, any copolymer        thereof, and any combination thereof.    -   Clause 39. The method of Clause 33, wherein the OAMB-polyamide        comprises an alkyl linker connecting the polyamide and the        optical absorber.    -   Clause 40. The method of Clause 39, wherein the alkyl linker has        2-18 carbons.    -   Clause 41. The method of one of claim 39, wherein the alkyl        linker has 2-6 carbons.    -   Clause 42. The method of Clause 33, wherein the emulsion        stabilizer is included in the mixture, and wherein at least some        of the solidified particles have a void comprising the emulsion        stabilizer at a void/polymer interface.    -   Clause 43. The method of Clause 42, wherein the emulsion        stabilizer comprises nanoparticles and the nanoparticles are        embedded in the void/polymer interface.    -   Clause 44. The method of Clause 42, wherein the void contains        the carrier fluid.    -   Clause 45. The method of Clause 33, wherein the solidified        particles further comprises elongated structures on the surface        of the solidified particles, wherein the emulsion stabilizer is        included in the mixture, and wherein the elongated structures        comprises the OAMB-polyamide with the emulsion stabilizer        associated with an outer surface of the elongated structures.    -   Clause 46. The method of Clause 33, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer forms a coating that covers less than 5% of the        surface of the solidified particles.    -   Clause 47. The method of Clause 33, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer forms a coating that covers at least 5% of the        surface of the solidified particles.    -   Clause 48. The method of Clause 33, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer forms a coating that covers at least 25% of the        surface of the solidified particles.    -   Clause 49. The method of Clause 33, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer forms a coating that covers at least 50% of the        surface of the solidified particles.    -   Clause 50. The method of Clause 33, wherein the OAMB-polyamide        is present in the mixture at 5 wt % to 60 wt % of the mixture.    -   Clause 51. The method of Clause 33, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer is present in the mixture at 0.05 wt % to 5 wt % by        weight of the OAMB-polyamide.    -   Clause 52. The method of Clause 33, wherein the emulsion        stabilizer is included in the mixture, and wherein emulsion        stabilizer comprises nanoparticles having an average diameter of        1 nm to 500 nm.    -   Clause 53. The method of Clause 33, wherein the carrier fluid is        selected from the group consisting of: silicone oil, fluorinated        silicone oils, perfluorinated silicone oils, polyethylene        glycols, paraffins, liquid petroleum jelly, vison oils, turtle        oils, soya bean oils, perhydrosqualene, sweet almond oils,        calophyllum oils, palm oils, parleam oils, grapeseed oils,        sesame oils, maize oils, rapeseed oils, sunflower oils,        cottonseed oils, apricot oils, castor oils, avocado oils, jojoba        oils, olive oils, cereal germ oils, esters of lanolic acid,        esters of oleic acid, esters of lauric acid, esters of stearic        acid, fatty esters, higher fatty acids, fatty alcohols,        polysiloxanes modified with fatty acids, polysiloxanes modified        with fatty alcohols, polysiloxanes modified with polyoxy        alkylenes, and any combination thereof.    -   Clause 54. The method of Clause 53, wherein the silicone oil is        selected from the group consisting of: polydimethylsiloxane,        methylphenylpolysiloxane, an alkyl modified        polydimethylsiloxane, an alkyl modified        methylphenylpolysiloxane, an amino modified        polydimethylsiloxane, an amino modified        methylphenylpolysiloxane, a fluorine modified        polydimethylsiloxane, a fluorine modified        methylphenylpolysiloxane, a polyether modified        polydimethylsiloxane, a polyether modified        methylphenylpolysiloxane, and any combination thereof.    -   Clause 55. The method of Clause 33, wherein the carrier fluid        has a viscosity at 25° C. of 1,000 cSt to 150,000 cSt.    -   Clause 56. The method of Clause 33, wherein the carrier fluid        has a density of 0.6 g/cm3 to 1.5 g/cm3.    -   Clause 57. The method of Clause 33, wherein mixing occurs in an        extruder.    -   Clause 58. The method of Clause 33, wherein mixing occurs in a        stirred reactor.    -   Clause 59. The method of Clause 33, wherein the mixture further        comprises a surfactant.    -   Clause 60. The method of Clause 33, wherein the particles have a        D10 of about 0.1 μm to about 125 μm, a D50 of about 0.5 μm to        about 200 μm, and a D90 of about 3 μm to about 300 μm, wherein        D10<D50<D90.    -   Clause 61. The method of Clause 33, wherein the particles have a        diameter span of about 0.2 to about 10.    -   Clause 62. The method of Clause 33, wherein the particles have a        D10 of about 5 μm to about 30 μm, a D50 of about 30 μm to about        70 μm, and a D90 of about 70 μm to about 120 μm, wherein        D10<D50<D90.    -   Clause 63. The method of Clause 62, wherein the particles have a        diameter span of about 1.0 to about 2.5.    -   Clause 64. The method of Clause 33, wherein the particles have a        D10 of about 25 μm to about 60 μm, a D50 of about 60 μm to about        110 μm, and a D90 of about 110 μm to about 175 μm, wherein        D10<D50<D90.    -   Clause 65. The method of Clause 64, wherein the particles have a        diameter span of about 0.6 to about 1.5.    -   Clause 66. The method of Clause 33, wherein the particles have a        D10 of about 75 μm to about 125 μm, a D50 of about 100 μm to        about 200 μm, and a D90 of about 125 μm to about 300 μm, wherein        D10<D50<D90.    -   Clause 67. The method of Clause 66, wherein the particles have a        diameter span of about 0.2 to about 1.2.    -   Clause 68. The method of Clause 33, wherein the solidified        particles have a circularity of about 0.90 to about 1.0.    -   Clause 69. The method of Clause 33, wherein the solidified        particles have a Hausner ratio of about 1.0 to about 1.5.    -   Clause 70. The method of Clause 33, wherein the nanoparticles        comprise oxide nanoparticles.    -   Clause 71. The method of Clause 33, wherein the nanoparticles        comprise carbon black.    -   Clause 72. The method of Clause 33, wherein the nanoparticles        comprise polymer nanoparticles.    -   Clause 73. A composition comprising: particles comprising a        polyamide having an optical absorber pendent from a backbone of        the polyamide (OAMB-polyamide) and having a circularity of about        0.90 to about 1.0.    -   Clause 74. The composition of Clause 73, wherein the particles        further comprise a thermoplastic polymer that is not the        OAMB-polyamide.    -   Clause 75. The composition of Clause 73, wherein the particles        further comprise the polyamide but without an optical absorber        pendent therefrom.    -   Clause 76. The composition of Clause 73, wherein the emulsion        stabilizer is included in the mixture, and wherein the particles        further comprise an emulsion stabilizer associated with an outer        surface of the particles.    -   Clause 77. The composition of Clause 73, wherein the emulsion        stabilizer is included in the mixture, and wherein at least some        of the particles have a void comprising the emulsion stabilizer        at a void/polymer interface.    -   Clause 78. The composition of Clause 77, wherein the emulsion        stabilizer comprises nanoparticles and the nanoparticles are        embedded in the void/polymer interface.    -   Clause 79. The composition of Clause 77, wherein the void        contains the carrier fluid.    -   Clause 80. The composition of Clause 73, wherein the solidified        particles further comprises elongated structures on the surface        of the solidified particles, wherein the emulsion stabilizer is        included in the mixture, and wherein the elongated structures        comprises the OAMB-polyamide with the emulsion stabilizer        associated with an outer surface of the elongated structures.    -   Clause 81. The composition of Clause 73, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer forms a coating that covers less than 5% of the        surface of the solidified particles.    -   Clause 82. The composition of Clause 73, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer forms a coating that covers at least 5% of the        surface of the solidified particles.    -   Clause 83. The composition of Clause 73, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer forms a coating that covers at least 25% of the        surface of the solidified particles.    -   Clause 84. The composition of Clause 73, wherein the emulsion        stabilizer is included in the mixture, and wherein the emulsion        stabilizer forms a coating that covers at least 50% of the        surface of the solidified particles.    -   Clause 85. The composition of Clause 73, wherein the emulsion        stabilizer is included in the mixture, and wherein emulsion        stabilizer comprises nanoparticles having an average diameter of        1 nm to 500 nm.    -   Clause 86. The composition of Clause 73, wherein the particles        have a D10 of about 0.1 μm to about 125 μm, a D50 of about 0.5        μm to about 200 μm, and a D90 of about 3 μm to about 300 μm,        wherein D10<D50<D90.    -   Clause 87. The composition of Clause 73, wherein the particles        have a diameter span of about 0.2 to about 10.    -   Clause 88. The composition of Clause 73, wherein the particles        have a D10 of about 5 μm to about 30 μm, a D50 of about 30 μm to        about 70 μm, and a D90 of about 70 μm to about 120 μm, wherein        D10<D50<D90.    -   Clause 89. The composition of Clause 88, wherein the particles        have a diameter span of about 1.0 to about 2.5.    -   Clause 90. The composition of Clause 73, wherein the particles        have a D10 of about 25 μm to about 60 μm, a D50 of about 60 μm        to about 110 μm, and a D90 of about 110 μm to about 175 μm,        wherein D10<D50<D90.    -   Clause 91. The composition of Clause 90, wherein the particles        have a diameter span of about 0.6 to about 1.5.    -   Clause 92. The composition of Clause 73, wherein the particles        have a D10 of about 75 μm to about 125 μm, a D50 of about 100 μm        to about 200 μm, and a D90 of about 125 μm to about 300 μm,        wherein D10<D50<D90.    -   Clause 93. The method of Clause 92, wherein the particles have a        diameter span of about 0.2 to about 1.2.    -   Clause 62. The composition of Clause 73, wherein the solidified        particles have a Hausner ratio of about 1.0 to about 1.5.

Unless otherwise indicated, all numbers expressing quantities ofingredients, properties such as molecular weight, reaction conditions,and so forth used in the present specification and associated claims areto be understood as being modified in all instances by the term “about.”Accordingly, unless indicated to the contrary, the numerical parametersset forth in the following specification and attached claims areapproximations that may vary depending upon the desired propertiessought to be obtained by the incarnations of the present inventions. Atthe very least, and not as an attempt to limit the application of thedoctrine of equivalents to the scope of the claim, each numericalparameter should at least be construed in light of the number ofreported significant digits and by applying ordinary roundingtechniques.

One or more illustrative incarnations incorporating one or moreinvention elements are presented herein. Not all features of a physicalimplementation are described or shown in this application for the sakeof clarity. It is understood that in the development of a physicalembodiment incorporating one or more elements of the present invention,numerous implementation-specific decisions must be made to achieve thedeveloper's goals, such as compliance with system-related,business-related, government-related and other constraints, which varyby implementation and from time to time. While a developer's effortsmight be time-consuming, such efforts would be, nevertheless, a routineundertaking for those of ordinary skill in the art and having benefit ofthis disclosure.

While compositions and methods are described herein in terms of“comprising” various components or steps, the compositions and methodscan also “consist essentially of” or “consist of” the various componentsand steps.

To facilitate a better understanding of the embodiments of the presentinvention, the following examples of preferred or representativeembodiments are given. In no way should the following examples be readto limit, or to define, the scope of the invention.

EXAMPLES Prophetic Example 1 Preparation of Modified-Alizarin

About 1.5 mmol DMAP was added to a stirred solution of about 5.5 mmolbromoacetate in DMSO. The mixture was stirred at room temperature for 5minutes before adding 6.0 mmol DCC. After 10 minutes, 5.5 mmol alizarinwas added and stirred for 4 hours. The organic layer was separated,mixed with ethyl acetate, washed with water, and dried over Na₂SO₄.After evaporation of the solvent, the crude residue was purified bycolumn chromatography using cyclohexaneEtOAc (10:1) as an eluent.

Prophetic Example 2 Preparation of Alizarin-Modified Nylon

Nylon 6, nylon 6,6, nylon 6,10, and nylon 12 were modified with themodified-alizarin prepared in Example 1.

150 mL DMSO and 5.5 mmol nylon polymer were mixed. To the mixture, 5.5mmol potassium t-butoxide was added. The mixture was blanketed withargon and heated to a temperature of 150° C. The suspension was allowedto mix at 150° C. for about 1 hour or until most of nylon was dissolved.Next, 5.5 mmol modified alizarin was added to the flask, and thereaction was allowed to proceed overnight. The next day the reactionmixture was cooled to room temperature and precipitated into 800 mL ofdeionized water. The mixture comprising alizarin-modified nylon,unmodified nylon, and unreacted modified-alizarin was then isolated byfiltration and repeatedly washed with water to remove the DMSO solvent.Next, the solid was rinsed with methanol to remove the water thenstirred in hexanes to remove the unreacted modified-alizarin. Theresulted nylon mixture (modified and unmodified) was then isolated byfiltration and allowed to dry in a vacuum oven at 60° C. overnight.

These examples illustrate that optical absorbers can be modified andthen reacted with polyamides to produce optical absorber-modifiedpolyamides.

Therefore, the present invention is well adapted to attain the ends andadvantages mentioned as well as those that are inherent therein. Theparticular examples and configurations disclosed above are illustrativeonly, as the present invention may be modified and practiced indifferent but equivalent manners apparent to those skilled in the arthaving the benefit of the teachings herein. Furthermore, no limitationsare intended to the details of construction or design herein shown,other than as described in the claims below. It is therefore evidentthat the particular illustrative examples disclosed above may bealtered, combined, or modified and all such variations are consideredwithin the scope and spirit of the present invention. The inventionillustratively disclosed herein suitably may be practiced in the absenceof any element that is not specifically disclosed herein and/or anyoptional element disclosed herein. While compositions and methods aredescribed in terms of “comprising,” “containing,” or “including” variouscomponents or steps, the compositions and methods can also “consistessentially of” or “consist of” the various components and steps. Allnumbers and ranges disclosed above may vary by some amount. Whenever anumerical range with a lower limit and an upper limit is disclosed, anynumber and any included range falling within the range is specificallydisclosed. In particular, every range of values (of the form, “fromabout a to about b,” or, equivalently, “from approximately a to b,” or,equivalently, “from approximately a-b”) disclosed herein is to beunderstood to set forth every number and range encompassed within thebroader range of values. Also, the terms in the claims have their plain,ordinary meaning unless otherwise explicitly and clearly defined by thepatentee. Moreover, the indefinite articles “a” or “an,” as used in theclaims, are defined herein to mean one or more than one of the elementthat it introduces.

What is claimed:
 1. A method comprising: providing a mixture comprisinga polyamide having an optical absorber pendent from a backbone of thepolyamide via a backbone nitrogen atom (OAMB-polyamide), a carrier fluidthat is immiscible with the OAMB-polyamide, and optionally, an emulsionstabilizer; mixing the mixture at a temperature greater than a meltingpoint or softening temperature of the OAMB-polyamide and at a shear ratesufficiently high to disperse the OAMB-polyamide in the carrier fluid;and cooling the mixture to below the melting point or softeningtemperature of the OAMB-polyamide to form particles in solidified formcomprising the OAMB-polyamide and, if included in the mixture, theemulsion stabilizer is associated with an outer surface of theparticles; wherein the particles have a D10 of about 0.1 μm to about 125μm, a D50 of about 0.5 μm to about 200 μm, and a D90 of about 3 μm toabout 300 μm, wherein D10<D50<D90.
 2. The method of claim 1, wherein theemulsion stabilizer is included in the mixture.
 3. The method of claim2, wherein at least some of the particles have a void comprising theemulsion stabilizer at a void/polymer interface.
 4. The method of claim2, wherein the emulsion stabilizer comprises nanoparticles.
 5. Themethod of claim 3, wherein the void contains carrier fluid.
 6. Themethod of claim 1, wherein the mixture further comprises a thermoplasticpolymer that is not the OAMB-polyamide.
 7. The method of claim 6,wherein the thermoplastic polymer comprises the polyamide but withoutthe optical absorber pendent therefrom.
 8. The method of claim 1,wherein the optical absorber is from a family selected from the groupconsisting of rhodamines, fluoresceins, coumarins, naphthalimides,benzoxanthenes, acridines, cyanines, oxazins, phenanthridine, pyrroleketones, benzaldehydes, polymethines, triarylmethanes, anthraquinones,pyrazolones, quinophthalones, carbonyl dyes, diazo dyes, perinones,diketopyrrolopyrrole (DPP), dioxazine dyes, phthalocyanines,indanthrenes, benzanthrone, violanthrones, azo dyes, phthalocyaninedyes, quinacridone dyes, anthraquinone dyes, dioxagine dyes, indigodyes, thioindigo dyes, perinone dyes, perylene dyes, isoindolene dyes,aromatic amino acids, flavins, derivatives of pyridoxyl, derivatives ofchlorophyll, and any combination thereof.
 9. The method of claim 1,wherein the polyamide is selected from the group consisting ofpolycaproamide, poly(hexamethylene succinamide), polyhexamethyleneadipamide, polypentamethylene adipamide, polyhexamethylene sebacamide,polyundecamide, polydodecamide, polyhexamethylene terephthalamide, nylon10,10, nylon 10,12, nylon 10,14, nylon 10,18, nylon 6,18, nylon 6,12,nylon 6,14, nylon 12,12, a semi-aromatic polyamide, an aromaticpolyamide, any copolymer thereof, and any combination thereof.
 10. Themethod of claim 1, wherein the OAMB-polyamide comprises an alkyl linkerconnecting the backbone of the polyamide to the optical absorber. 11.The method of claim 10, wherein the alkyl linker has 2-18 carbons. 12.The method of claim 10, wherein the alkyl linker has 2-6 carbons. 13.The method of claim 1, wherein the particles have a diameter span ofabout 0.2 to about
 10. 14. The method of claim 1, wherein the particleshave a circularity of about 0.90 to about 1.0.
 15. The method of claim1, wherein the optical absorber is pendent from the backbone of thepolyamide by an ester bond.
 16. The method of claim 1, wherein thecarrier fluid is selected from the group consisting of a silicone oil, afluorinated silicone oil, a perfluorinated silicone oil, a polyethyleneglycol, an alkyl-terminal polyethylene glycol, tetraethylene glycoldimethyl ether, a paraffin, a liquid petroleum jelly, a vison oil, aturtle oil, a soya bean oil, perhydrosqualene, a sweet almond oil, acalophyllum oil, a palm oil, a parleam oil, a grapeseed oil, a sesameoil, a maize oil, a rapeseed oil, a sunflower oil, a cottonseed oil, anapricot oil, a castor oil, an avocado oil, a jojoba oil, an olive oil, acereal germ oil, an ester of lanolic add, an ester of oleic add, anester of lauric add, an ester of stearic add, a fatty ester, a fattyadd, a fatty alcohol, a polysiloxane modified with fatty adds, apolysiloxane modified with fatty alcohols, a polysiloxane modified withpolyoxyalkylenes, and any combination thereof.
 17. The method of claim1, wherein the carrier fluid is selected from the group consisting of asilicone oil, a fluorinated silicone oil, a perfluorinated silicone oil,and any combination thereof.
 18. The method of claim 4, wherein thenanoparticles comprise oxide nanoparticles.
 19. A method comprising:providing a mixture comprising a polyamide having an optical absorberpendent from a backbone of the polyamide (OAMB-polyamide), nanoparticlesas an emulsion stabilizer, and a carrier fluid that is immiscible withthe OAMB-polyamide; mixing the mixture at a temperature greater than amelting point or softening temperature of the OAMB-polyamide and at ashear rate sufficiently high to disperse the OAMB-polyamide in thecarrier fluid; and cooling the mixture to below the melting point orsoftening temperature of the OAMB-polyamide to form particles insolidified form comprising the OAMB-polyamide and the nanoparticles areassociated with an outer surface of the particles.
 20. The method ofclaim 19, wherein the nanoparticles comprise oxide nanoparticles.